Crystal transformation from the a- to the b-form upon tensile
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材料英语作文河流到达海洋而是沿途的风景全文共3篇示例,供读者参考篇1The Winding Path to the Sea: A River's JourneyThey say that a river's destiny is not a better destiny, but rather the journey itself. As a high school student living in a small town nestled along the banks of the Willamette River in Oregon, I've come to understand the profound truth in those words.The Willamette carves its path through valleys and canyons, cities and farmlands, ever pushing forward yet meandering with a sense of grace and patience. From its humble origins as a trickle of snowmelt high in the Cascade Mountains, it grows in strength and determination with each new tributary that feeds its flow.In my youth, I would spend endless summer days wandering the river's edge, my toes digging into the cool, damp soil. The Willamette was my loyal companion, a steadfast presence that colored the background of my formative years. Yet I failed to fully grasp its magnificence until I reached an age where I could reflect on the river's greater purpose.A river's journey is one of fusion - a uniting of waters from high and low, a singular path created by the joining of many streams. The Willamette collects the liquid stories of the Coastal and Cascade ranges, growing swollen with snow runoff, rain, and the outpourings of smaller brooks and creeks. Each new confluence introduces a fresh narrative, altering the river's flow while adding to its complexity.As the Willamette winds northward through Oregon's fertile valleys, it acts as an artery of life. Lush greenery lines the banks, bowing respectfully toward the riverside as if in humble gratitude for the river's life-giving waters. Farms and vineyards flourish on the nutrient-rich soils, sustained by the Willamette's bounty. Even cities like Portland have evolved along the river's sinuous curves, their skylines reflecting in the waters that enabled their existence.To travel beside a river is to bear witness to a grand transformation. The higher I ascend along its path, the more I'm transported through epochs of ecological evolution. From the lush rainforests of its headwaters to the arid high desert landscapes in the east, the Willamette's banks host anever-changing ecosystem parade.The river is also a study in raw, unbridled power. I've witnessed its fury during the spring floods, raging currents tearing away at the banks and obliterating all in their wake. Like the human experience, the river's journey oscillates between peace and upheaval, calm and chaos. Yet it continues ever forward with an indomitable sense of purpose.For as the Willamette flows, so too does the march of civilization. Pioneer settlements emerged along the banks, their sehr inhabitants recognizing the river's importance as a source of food, water, and transportation. Even today, the reaction has to be carried from interior Oregon to the Pacific ports, the river's currents supporting commerce and cultural exchange.Often at night, I'll sit quietly and listen to the Willamette's song - the eternal rush of water over rocks and fallen logs. It's a lyrical melody that spans eons, dating back to the very origins of this magnificent waterway. The more I attune my senses, the more the river's rhythm becomes a part of my own innermost beat and breath.In those transcendent moments, I'm reminded that the Willamette's journey is truly the journey of life itself. It is a river of dreamers and pioneers, of prospectors and homesteaders. It haswitnessed epochs of volcanic catastrophe and regrowth, the comings and goings of great forests and deserts and peoples.Most importantly, the Willamette's ceaseless flow teaches us that no purpone or destination holds more significance than our daily experiences. It is the journey - with all its meanderings and oscillations between turbulence and peace - that holds the ultimate meaning.For me, the Willamette's path will eventually culminate in the vast expanse of the Pacific Ocean. Its waters will merge with the sea's rolls and currents, dispersing across planet Earth in a new cycle. Yet the river's true legacy lies not in that final destination, but in every mile along the way. Itlawksoes in the sunbeams glittering on the waters, the rushes swaying gently in the riverside breezes, and the splendor of another perfect sunset reflecting from its mirrored surface.The journey of a river is a metaphor for the human condition - a compelling call to cherish each passing current, rapid, andof our existence. Like the Willamette, we are constantly in motion yet shaped by the scenery waking across our paths. Our individual stories accte to form the greater river of humankind, ever ebbing and merging toward new conceptions and experiences.So go ahead and dip your toes into the metaphoric waters of your own life's river. Let the currentsonly carry you forward while opening your soul to the profound revelations unfolding at every bend. The ultimate destination matters little compared to the beauty witnessed in the journey itself.篇2The Winding Path to the Sea: A River's JourneyHave you ever really stopped to ponder the incredible journey that a river takes from its humble beginnings high up in the mountains all the way down to the vast, salty expanse of the ocean? It's a voyage filled with twists and turns, obstacles to overcome, and ever-changing scenery that paints a breathtaking tapestry of nature's grandeur. Join me as we trace the footsteps of a river, for it is not the ultimate destination that matters most, but rather the sights and experiences along the way.Our adventure begins at the river's source, a crystal-clear spring bubbling forth from the rocky embrace of a towering peak. Here, the water is pure and icy cold, untainted by the world below. As it trickles down the mountainside, it collects into a merry stream, dancing over mossy boulders and carving its way through the rugged terrain. The air is crisp and invigorating,filled with the scents of pine and wild flowers, a true feast for the senses.Gradually, the stream grows bolder, swelling with the contributions of countless tributaries that join its ranks. The once-gentle trickle transforms into a rushing torrent, crashing over craggy outcroppings and plunging into deep, narrow gorges. The thunderous roar of the water echoes through the valley, a primal symphony that resonates within our very bones. Here, the river is a force to be reckoned with, carving its path with relentless determination, sculpting the landscape with each passing year.As we descend further, the terrain begins to level out, and the river's fury subsides into a more tranquil flow. Emerald-green banks line its shores, dotted with willows that dip their slender branches into the cool, clear depths. Sunlight dances across the rip篇3The Journey of a River to the OceanI remember the first time I truly appreciated the sheer magnificence of a river. It was during a hiking trip with my family in the mountains, where a pristine stream gurgled and tumbledover rocks, its crystal-clear waters reflecting the dappled sunlight filtering through the canopy of trees. That day, I discovered that a river's true splendor lies not merely in its destination but in the journey itself – the ever-changing landscapes it traverses, the life it sustains, and the stories it whispers to those willing to listen.A river's voyage begins high up in the mountains, where melting snow and rainfall converge to form tiny rivulets. These delicate streams, no wider than a footpath, trickle down the slopes, weaving through crevices and cracks in the rock. As they descend, they merge and swell, gaining strength and momentum, until they become a formidable torrent carving its path through the rugged terrain.In the upper reaches, the river is a wild and untamed force, its waters cascading over towering cliffs in a breathtaking display of power. The roar of the falls echoes through the valleys, a primordial symphony that has played for eons. Here, the river's course is dictated by the immovable giants of stone, sculpting intricate patterns and forming deep pools where rainbows of mist dance in the sunlight.As the river continues its descent, it enters a more tranquil phase, meandering through verdant meadows and lush forests. Its banks are lined with a tapestry of vibrant wildflowers, theirpetals swaying gently in the breeze. The air is rich with the scents of pine and earth, and the melodic calls of birds accompany the river's soothing murmur.In these stretches, the river becomes a lifeline for countless species. Deer and elk come to quench their thirst, while bears and otters hunt for fish in the shallows. Dragonflies flit across the surface, their iridescent wings catching the light, and waterfowl glide gracefully, leaving rippling trails in their wake. The river sustains an entire ecosystem, a delicate balance of interdependence that has existed for millennia.As the river winds its way through the foothills and valleys, it encounters human settlements – quaint villages and bustling towns that have sprung up along its banks. Here, the river becomes a vital artery, providing water for drinking, irrigation, and industry. Its waters power mills and factories, turning great wooden wheels that once drove the local economy.In these urban stretches, the river takes on a different character, its banks lined with stone walls and promenades. Bridges arch gracefully overhead, connecting communities on either side, while parks and public spaces offer respite from the hustle and bustle of city life. The river becomes a gathering place,a hub of recreation and leisure, where people come to fish, swim, or simply bask in its tranquil beauty.Yet, even as it meanders through urban landscapes, the river retains its wild essence, a living reminder of nature's enduring presence. Its waters reflect the ever-changing sky, mirroring the vibrant hues of sunrise and sunset, the billowing clouds of an approaching storm, or the twinkling stars of a clear night.And so, the river continues its journey, winding its way through a tapestry of landscapes, each more captivating than the last. It passes through fertile farmlands, where fields of golden wheat and verdant vineyards stretch as far as the eye can see. It carves through arid deserts, where its waters become a lifeline for hardy plants and animals adapted to the harsh conditions.Finally, after traversing countless miles and overcoming innumerable obstacles, the river reaches its ultimate destination – the vast, unending expanse of the ocean. Here, its waters mingle with the salty brine, losing their individual identity but becoming part of a greater, more profound cycle.As I stand on the shore, watching the river's final moments before it merges with the sea, I am struck by the sheer majesty of its journey. From its humble beginnings as a trickle high in themountains to its triumphant arrival at the ocean, the river has witnessed and shaped the very fabric of the land.Its waters have nourished life, carved landscapes, and borne witness to the ebb and flow of civilizations. It has been a constant companion, a thread weaving through the tapestry of history, carrying with it the stories of all those who have walked along its banks.And as I gaze out over the vast expanse of the ocean, I realize that the river's journey is not truly over. Its waters will evaporate, rise into the clouds, and one day fall back to the earth as rain or snow, beginning the cycle anew. The river's voyage is an eternal one, a perpetual dance between land and sea, a testament to the enduring rhythm of nature.In that moment, I am filled with a profound sense of awe and reverence for the river and all that it represents. It is a reminder that life itself is a journey, a winding path filled withever-changing landscapes and experiences. And like the river, we must embrace the beauty and wonder of the voyage, for it is in the journey that we truly find meaning and fulfillment.。
adhesive[胶]allotropic[同素异形的amorphous[无定形的,非晶的anion[负离子]apuy[适当地]austenite[奥氏体]bainte「贝氏体binary isomorphous system[二元匀晶系统]Burgers vector[柏氏矢量]cadmium[镉]canon[正离子]carbide[碳化物Cast Iron[铸铁cementite[渗碳体]ceramic[陶瓷]chloride[氯chromium[铬]composite materials[复合材料cordinate system[坐标系统covalent bond[共价键crystal structure[晶体结构]crystallinity[结晶度ddiy[塑性deteriorative[劣化]dislocation[位错]edge dislocation[刃形位错]equilibrium[平衡]eutectic[共晶的eutectoid[共析的ferrite[铁素体fractional[分数的,部分的,相对的gain[晶粒grain boundary[晶界hase[相hexagonal dose-packed[密排六方的hexagonal[六方的]hypereutectoid[过共析hypoeutectoid[亚共析ion[硅Ionic Dond[离子键]isotherm[等温线lamellae[薄片]lattice[空间点阵,晶格]lever law[杠杆定律liquidus line[液相线martensite[马氏体]martensitic transformation[马氏体相变metallic bond[金属键]microstucture[显微组织monoclinic[单斜的nickel[镍nitride[氮化物]non-crystalline[非晶的]orthorhombic[正交的]parentheses[括孤]pearlite[珠光体periodic table[元素周期表phase diagram[相图]」phase transformation[相交]」point defect[点缺陷]polarize[极化polyethylene[聚乙烯polymerization[聚合]prism[棱镜]proeutectoid[先共析体provoke[诱发]reciprocal[倒数recrystallization[再结晶rhombohedral[菱方的screw dislocation[螺形位错]skew[歪斜]smal-(or low)angle grain boundary[小角度晶界sodium[钠solar cell [太阳能电池]solid solution strengthening[固溶强化solidus line[固相线solute[溶质solvus line[溶解度曲线spiral[螺旋形的]stifness[刚度]strucure[组织]synthesis[合成tetragonal[四方的tetrahedron[四面体thermoplastics[热塑性塑料]thermosets[热固性塑料tie linc[连接线]tilt boundary[倾侧晶界]translucent[半透明的]triclinic[三斜的troley[石油twin boundary[李晶界unit cell[晶胞vacancy[空位valence electron[价电子]Van de Waals bond[范德华键①材料科学是研究材料的加工、组织、性能和功能之间关系的科学。
Chap 11、Semiconductors11.1 (a) For a semiconductor, show that np product obtained fromEq.(11.27) is proportional to exp(-βE g ) and thus is independent of the position of the chemical potential μ in the bandgap.Eq.(11.27):(b) The law of mass action in semiconductors for reaction creatingpairs of electrons and holes [e.g., Eq.(11.28)] has the form n(T)P(T)∝exp(-βE g ). Explain the significance of this law. (Hint: The law of mass action is described in Section 4.6)Eq.(11.28): (c) Evaluate the np product at T=300K for Si with E g =1.11ev andm eds ﹡=1.05m and m hds ﹡=0.58m.11.2 Using Eq.(11.30) and m eds ﹡=1.05m and m hds ﹡=0.58m for Si,calculate the change in the position of the chemical potential µ in the energy gap of intrinsic Si between T=0 and 300K.Eq.(11.30): 11.3 Calculate the values of N c and N v as defined in Eq.(11.27) for Siat T=300K. The appropriate of density-of-states effective masses for Si are m eds ﹡=1.05m and m hds ﹡=0.58m.11.4 Consider a semiconductor with a bulk energy gap E g =1.5ev andgE v c i i e T N T N T p T n β-=)()()()()()(2/32)()2(2)()(μβμβπ----*===c c E c E B eds i e T N e T k T n T n m )()(2/32)()2(2)()(v v E v E B h ds i e T N e T k T p T p m ----*===μβμβπ **+=eds hdsB g m m T k E T ln 432)(μwith m e﹡=m h﹡=0.1m. Calculate the increase in the energy gap ofthis semiconductor when it is incorporated into the followingstructures:(a) A quantum well (d=2) with L x=10nm.(b) A quantum wire (d=1) with L x=L y=10nm(c) A quantum dot (d=0) with L x=L y=L z=10nm11.5 A Hall effect measurement is carried out on a rectangular barof a semiconductor with dimensions L x=0.04m (the directionof current flow ) and L y=L z=0.002m. When a current I x=5mAflows in the +x direction and a magnetic field B z=0.2T isapplied in the +z direction, the following voltages aremeasured: V x=6V and V y=+0.3mV (i.e., increasing in the +ydirection). Determine the following properties of thesemiconductor bar from these data :(a) The sign of the dominant charge carriers.(b) The concentration of the dominant charge carriers.(c) The electrical conductivity σ.(d) The mobility µ of the dominant charge carriers.11.6Using Eq.(11.59), estimate the increase △n in the electronconcentration in an n-type semiconductor due to the uniformabsorption of light with α=105m-1, I0=1W/m2, and hω=1e V, aquantum efficiency η=1, and a minority-carrier lifetime ηp=10-3s.Eq.(11.59): 11.7 Using the definition of the Hall mobility µH =︱ζR H ︱and theexpression for R H for an intrinsic semiconductor given in Eq.(11.49), show that µH =︱µh -µe ︱.Eq.(11.49): 11.8 Consider the structural transformation of a binary crystal ABfrom the hexagonal wurtzite crystal structure to the cubic zincblende crystal structure in which the density of the atoms remains constant. Find the lattice constant of the resulting cubic crystal if the lattice constants of the initial wurtzite crystal are a =0.3400nm and c =0.5552nm.11.11 List all of the local tetrahedral bonding units, A-B 4, which arepresent in the ternary semiconducting compounds Cu 2SiTe 3, Cu 3PS 4, and CuSi 2P 3. Note that each tetrahedron must contain an average of four bonding electrons per atom.11.13 Derive the expression for the shift △E of the electron energybands from one side of a p-n junction to the other under zero bias as given in Eq.(11.93). Calculate the magnitdde of the built-in electric potential V B =△E/e for Si at T=300K for N d =N a =2×1024m -3. Using these same parameters, calculate the depletion width d and the maximum electric field Q/∈A for a Si p-n junction at T=300 K.ωτηατω pp L I G p n 0)(==∆=∆)(e h eh H ne R μμμμ+-=Eq.(11.93): .Chap 12、Metals and Alloys 12.1 Referring to Section 12.5, show that the condition for the tangencyof the Fermi sphere to the Brillouin zone boundary for the FCC lattice is N =1.36.12.2 Derive Eq.:12.3 Derive Eq.:Chap 13、Ceramics13.1 For the silicon oxynitride compound Si 2N 2O, assume that Si, N,and O atoms have their usual valences (4, 3, and 2) and that the N and O atoms do not form covalent bonds with each other. (a) Given a local bonding unit Si-N x O y for Si with x+y =4,determine x (and y ) for this crystal structure.(b) What are the local bonding units for N and O?13.2 For the Si x N y O z ternary phase diagram, locate the followingcompounds :SiO 2, Si 3N 4, Si 2N 2O, and Si 3N 2O 3.13.3 Find the average number of bridging oxygens, b, and nonbridgingoxygens, n, for the following glasses:(a)CaO•SiO 2, and(b) soda-lime(i.e., 2CaO•3Na 2O•15SiO 2) n ia d B v c a d B g N N T k N N N N T k E E 2ln ln =+=∆)163253(02222∈-=πF F k e m k N U )]1(356[82202ws c ws Coul r r r Nze U --∈=πChap 14、Polymers14.1 A polymer whose viscoelastic properties are described byEq.(14.40) (i.e., the Maxwell model) is subjected to a time-dependent stress σ=σ0exp(-i ωt). Find the steady-state strain. Compare this result to that of a polymer that obeys the Voigt model, given by Eq. (14.37).Eq.(14.40): Eq. (14.37): 14.2 Consider an elastomer consisting of monomers that are opticallyanisotropic [i.e., they have a polarizability α11(ω) for light parallel to the chain axis and α┴(ω) for light polarized perpendicular to the chain axis]. Assume that there are N chains per unit volume. Let )(ωn be the mean index of refraction of the material. The elastomer is stretched with a steching parameter s , as defined in Secti on 14.5. Show that the elastomer will have a birefringence given by)]()()[1()(]2)([452)()()(112211ωαωαωωπωωωδ⊥--⊥--+=-=s s n n N n n nObtain an expression for the stress optical coefficient. C≡δn(ω)/ζ, where ζ is the applied stress.Chap 15、Dielectric and Ferroelectric Materials∙∙=+εησσG ηστεε=+∙15.1 Given the Landau free-energy density for a ferroelectric of the form Where b>c. Let a=a 0(T-T C ) and assume that b and c are constant. Find P z and χ as a function of T for the state of thermal equilibrium. 15.2 Design a piezoelectric actuator that can be used to sweep anSTM head over the surface of a solid. What is the area that can practically be covered?15.3 Adapt Weiss molecular field theory (see Chapter 9) to describe aferroelectric. Assume that there are just two orientations for the electric-dipole moment of a unit cell and that NN cells interact via an exchange interaction. Obtain the hysteresis curve and values for the coercive field E c , saturation polarization P sat , and remanent polarization P rem .15.4 BaTiO 3 is a paraelectric for T>T C =130℃ and has a Curie constantC=76,000K.(a)If the lattice constant for the cubic unit cell of BaTiO 3 is a=0.401nm, calculate the electric-dipole moment µ of this unit cell. (b)What would the corresponding polarization P=µn be at T=0 K?Chap 16、Superconductors16.1 (a) Derive expression for the difference in entropy△S(T)=S n (T)-S s (T) and the difference in specific heatZ y x x z z y z y x o EP P P P P P P c P P P b P a g g -+++++++=)(2)(422222224442△C(T)=C n (T)-C s (T) between the normal and superconducting states in terms of the critical magnetic field H c (T) and its first derivative dH c /dT and second derivative d 2H c /dT 2. [Hint: Use Eq.(16.3) and standard thermodynamic relationships.](b) Evaluate these expressions for △S(T) and △C(T) for the case where H c (T) can be approximated by H c0[1-(T/T c )2] and show that : (ⅰ) △S(T c )=△S(0)=0(ⅱ) △S(T)>0 for 0<T<T c(ⅲ)△C(T c )=-4µ0H c02/T c . Calculate △C(T c ) from this expressionusing T c = 1.175 K and H c0 = 105 Oe = 8360 A/m for Al and compare with the measured result -225 Jm -3K -1 for Al.(ⅳ) △C=0 for T=T c /3 and T=0K.Eq.(16.3): 16.2 (a) Using Eq.(16.5), calculate the condensation energy in J/m 3 and ineV per electron at T=0K for the superconductor Pb for which H c0=6.39×104A/m.(b) Compare your result from part (a) with the expression ε(0)(ε(0)/E F ) where the superconducting energy gap 2ε(0) = 2.6 meV for Pb. Here ε(0)/E F is the fraction of conduction elections whose energies are actually affected by the condensation .Eq.(16.5): 16.3 Consider the London penetration depth λL defined in Eq.(16.10).⎰+=-=H s s s s H T G dH H M T G T H G 02002),0()(),0(),(μμ2)(),0(),0(20T H T G T G c s n μ=-(a) Calculate λL (0K) for the superconducting Al, Pb, and Nb. (b) If a superconductor has a London penetration depth λL (0K)=200nm, what is the concentration n s of superconducting electrons at T=0.5T c .Eq.(16.10): 16.4 When transport current i flows through a superconducting wireof radius R, its path is confined to a region of thickness λ, the penetration depth, just inside the surface of the wire.(a) In this case show that the critical current density J c =i c /A eff is independent of R and can be expressed in terms of the critical field H c by J c =H c /λ. Here A eff is the effective area through which the current flows, with A eff <<πR 2.(b) Calculate J c for superconducting Pb at T=0K. [Note: H c0 = 803 Oe = 63919 A/m and λ(0) = 39 nm](c) Sketch J c (T)/J c (0) from T = 0 K to T c using the temperature dependencies of H c and λ given in Eqs.(16.6) and (16.11), respectively .Eq.(16.6):Eq.(16.11): 16.5 A type Ⅱ superconductor has T c =125k, ΘD =250K, and κ(T c )=50. Onthe basis of standard theories [free-electron model, Debye model, BCS theory, G-L theory, Pauli limit for H c2 given in Eq.(16.33)], 20)()(e T n mT s L μλ=)1()(220c c c T T H T H -=4)/(1)0()(c L L T T T -=λλestimate the following:(a)The superconducting energy gap 2ε(0).(b) The upper critical field H c2(0)=H p .(c)The co herence length ξ(0) and the penetration depth λ(0).(d)The thermodynamic critical field H c0=H c (0).(e)The coefficients γ and A of the electronic and phonon contributions to the specific heat , γT and AT 3, respectively.Eq.(16.33): 16.7 Use Eq.(16.20) to find the limiting values of λ(l ) and ξ(l ) (a) in theclean limit where the electron mean free path l >>ξ0, and (b) in the dirty limit where l <<ξ0.Eq.(16.20): and 16.8 (a) Calculate the density of vortices per unit area B/Φ0 for thefollowing values of B, the average flux density present in the mixed state of a superconductor. Take H c2=1.6MA/m.(i) B = μ0H c2/2. (ii) B ≈ B c2 = μ0H c2.(b)Calculate the average separation d between the vortices from your answers in part (a) and compare your answers with the conherence length ξ. [Hint: You can obtain ξ with the help of Eq.(16.22).]Eq.(16.22): 16.10 Calculate the number of holes N hole per Cu ion in the CuO 2copper-oxygen layers in the superconductor YBa 2Cu 3O 7-x for the Bp T T H μμε0)()(≈l l 11)(10+=ξξll ξλλ+∞=1)()()(2)(2002T T H c ξπμΦ=cases of x = 0, 0.25, and 0.5. Assume the following ionic charge states for the ions in this structure: Y 3+, Ba 2+, Cu 2+, and O 2-.16.11 For the compound with the chemical formula La 1.7Sr 0.3CuO 3.9:(a)what is the total number of electrons per formula unit outside closed shells?(b)How many electrons are contributed by each ion to the CuO 2 layers?(c)what is the average valence of the copper atoms?(d)Assuming that all copper ions have a charge of +2e, what is the number of holes per formula unit?16.12 Derive Eq.(16.33) for the Pauli limiting field H p by settingG n (H)=G s (H) at H=H p and using the Pauli paramagneticsusceptibility χp =µ0µB 2ρ(E F ) of the conduction electrons in thenormal state. [Hint: Use G n (H)-G n (0)=-µ0χp H 2/2, and the BCS resultG n (0)-G s (0)=ρ(E F )ε(0)2/2.]Eq.(16.33):Chap 17、Magnetic Materials17.1 Consider a single-domain uniaxial ferromagnetic particlemagnetized along its easy axis with M=M s in zero applied magnetic field. The magnetic anisotropy energy density is given by E a =K sin 2θ where K >0 and θ is the angle between the B p T T H μμε0)()(≈magnetization M and the easy axis. A magnetic field H is now applied at 90° to the easy axis.(a)Show that the sum of the anisotropy and magnetostatic energy densities for this particle is u(θ)=K sin 2θ-µ0MHsinθ.(b)Find the angle θ be tween M and the easy axis as a function of the magnitude of the field H by minimizing uwith respect to θ .(Note that it will be important to check for the stability of the solution by requiring that ∂2u/∂θ2>0.)(c) Show that the resulting magnetization curve (i.e., the plot of thecomponent of M in the direction of H versus the applied field H ) is a straight line (with slop χ=µ0M 2s /2K ) up to H =H k =2k/µ0M s , at which point the magnetization is saturated in the direction of H . Here H k is the effective magnetic anisotropy field in Eq.(17.14).Eq.(17.14): 17.4 Prove that when the shape anisotropy constant K s is <0 (i.e., whenN ⊥<N 11), the magnetization M for a ferromagnetic film will lie in the plane of the film .17.5 Calculate the radius at which a spherical Fe particle behavessuperparamagnetically at T =300K by setting K 1V=K B T , where K 1≈4.2×104J/m 3 is the first-order magnetocrystalline anisotropy coefficient for Fe and V is the volume of the sphere.17.6 Calculate t he increase in temperature ΔT of a magnetic material withsK M KH 02μ=a square magnetization loop, with M s =1370KA/m and H c =1100kA/m, when the loop is traversed once, Assume that the material is thermally-isolated from its surroundings and that its specific heat is 4×106J/m 3K.17.7 For a magnetically isotropic m aterial with magnetostriction λ, provethat B 2(C 11-C 12)=2B 1C 44. Show, in fact, that if the material is also elastically isotropic, then B 1=B 2. (Hint: See Section 10.8)17.8 Show that B (t) and M (t) both lag the applied magnetic fieldH(t )=H 0e -iωt by the same phas e angle δ when µ0H 0<<B 0cosδ. [Hint: Start by substituting the expressions for B (t) and M (t) from Eq.(17.33) into the expression B =µ0(H+M).]Eq.(17.33): andChap 18、Optical Materials18.1 Suppose that a quantum dot has the shape of a two-dimensionalcircular disk. A model that is often used to describe the potential of an electron confined in such a dot is V(r)=m ﹡ω02r 2/2. Suppose a magnetic induction B is imposed perpendicular to the plane of the dot. Show that the electron energy levels are given by the formula where n=0, 1, 2,…………and l=……, -2, -1, 0, 1, 2,……..18.2 Consider a Lorentz oscillator model for an electron moving in )(0)(δω+-=t i e B t B )(0)(φω+-=t i e M t M **-+++=m eB l m eB l n E l n 2)2()()12(220, ωone-dimensional anharmonic potential described by the Toda potential V(x)=Ae -ax +Bx, where A, a and B are constants. The equation of motion isDerive expressions for the linear polarization P , at frequency ω and the nonlinear polarization at frequency 2ω, P (2ω).18.3 Consider a particle of mass m moving in the anharmonicsymmetric potential V(x)=Acosh[a(x-x o )] subject to a damping force –γv and a driving force qE cosωt . Find the Fourier coefficients for the dipole moment at frequencies ω and 3ω. 18.4 Using Vegard′s law , derive an expression for the bandgap energyE g (x,y) of a layer of In 1-x Ga x As y P 1-y which is lattice matched to an InP substrate. Compare your expression with the experimental result given in Eq.(18.15) and comment on any differences.Eq.(18.15): E g =1.35-0.72y+0.12y 2 eVt qE e e aA dtdx dt x d m o ax ax ωγcos )()(22+-=+--。
托福阅读TPO20(试题+答案+译文)第3篇:FossilPreservationTPO是我们常用的托福模考工具,对我们的备考很有价值,下面小编给大家带来托福阅读TPO20(试题+答案+译文)第3篇:Fossil Preservation。
托福阅读原文【1】When one considers the many ways by which organisms are completely destroyed after death, it is remarkable that fossils are as common as they are. Attack by scavengers and bacteria, chemical decay, and destruction by erosion and other geologic agencies make the odds against preservation very high. However, the chances of escaping complete destruction are vastly improved if the organism happens to have a mineralized skeleton and dies in a place where it can be quickly buried by sediment. Both of these conditions are often found on the ocean floors, where shelled invertebrates (organisms without spines) flourish and are covered by the continuous rain of sedimentary particles. Although most fossils are found in marine sedimentary rocks, they also are found in terrestrial deposits left by streams and lakes. On occasion, animals and plants have been preserved after becoming immersed in tar or quicksand, trapped in ice or lava flows, or engulfed by rapid falls of volcanic ash.【2】The term "fossil" often implies petrifaction, literally a transformation into stone. After the death of an organism, the soft tissue is ordinarily consumed by scavengers and bacteria. The empty shell of a snail or clam may be left behind, and if it is sufficiently durable and resistant to dissolution, it may remain basically unchanged for a long period of time. Indeed, unaltered shells of marine invertebrates are known from deposits over 100million years old. In many marine creatures, however, the skeleton is composed of a mineral variety of calcium carbonate called aragonite. Although aragonite has the same composition as the more familiar mineral known as calcite, it has a different crystal form, is relatively unstable, and in time changes to the more stable calcite.【3】Many other processes may alter the shell of a clam or snail and enhance its chances for preservation. Water containing dissolved silica, calcium carbonate, or iron may circulate through the enclosing sediment and be deposited in cavities such as marrow cavities and canals in bone once occupied by blood vessels and nerves. In such cases, the original composition of the bone or shell remains, but the fossil is made harder and more durable. This addition of a chemically precipitated substance into pore spaces is termed "permineralization."【4】Petrifaction may also involve a simultaneous exchange of the original substance of a dead plant or animal with mineral matter of a different composition. This process is termed " replacement" because solutions have dissolved the original material and replaced it with an equal volume of the new substance. Replacement can be a marvelously precise process, so that details of shell ornamentation, tree rings in wood, and delicate structures in bone are accurately preserved.【5】Another type of fossilization, known as carbonization, occurs when soft tissues are preserved as thin films of carbon. Leaves and tissue of soft-bodied organisms such as jellyfish or worms may accumulate, become buried and compressed, and lose their volatile constituents. The carbon often remains behind as a blackened silhouette.【6】Although it is certainly true that the possession of hardparts enhances the prospect of preservation, organisms having soft tissues and organs are also occasionally preserved. Insects and even small invertebrates have been found preserved in the hardened resins of conifers and certain other trees. X-ray examination of thin slabs of rock sometimes reveals the ghostly outlines of tentacles, digestive tracts, and visual organs of a variety of marine creatures. Soft parts, including skin, hair, and viscera of ice age mammoths, have been preserved in frozen soil or in the oozing tar of oil seeps.【7】The probability that actual remains of soft tissue will be preserved is improved if the organism dies in an environment of rapid deposition and oxygen deprivation. Under such conditions, the destructive effects of bacteria are diminished. The Middle Eocene Messel Shale (from about 48 million years ago) of Germany accumulated in such an environment. The shale was deposited in an oxygen-deficient lake where lethal gases sometimes bubbled up and killed animals. Their remains accumulated on the floor of the lake and were then covered by clay and silt. Among the superbly preserved Messel fossils are insects with iridescent exoskeletons (hard outer coverings), frogs with skin and blood vessels intact, and even entire small mammals with preserved fur and soft tissue.托福阅读试题1.The word "agencies" in the passage (paragraph 1) is closest in meaning tobinations.B.problems.C.forces.D.changes.2.In paragraph 1, what is the author's purpose in providingexamples of how organisms are destroyed?A.To emphasize how surprising it is that so many fossils exist.B.To introduce a new geologic theory of fossil preservation.C.To explain why the fossil record until now has remained incomplete.D.To compare how fossils form on land and in water.3.The word "terrestrial" in the passage (paragraph 1) is closest in meaning tond.B.protected.C.alternative.D.similar.4.Which of the sentences below best expresses the essential information in the highlighted sentence in the passage (paragraph 2)? Incorrect choices change the meaning in important ways or leave out essential information.A.When snail or clam shells are left behind, they must be empty in order to remain durable and resist dissolution.B.Although snail and clam shells are durable and resist dissolving, over time they slowly begin to change.C.Although the soft parts of snails or clams dissolve quickly, their hard shells resist dissolution for a long time.D.Empty snail or clam shells that are strong enough not to dissolve may stay in their original state for a long time.5.Why does the author mention "aragonite" in the passage (paragraph 2)?A.To emphasize that some fossils remain unaltered for millions of years.B.To contrast fossil formation in organisms with soft tissue and in organisms with hard shells.C.To explain that some marine organisms must undergo chemical changes in order to fossilize.D.To explain why fossil shells are more likely to survive than are fossil skeletons.6.The word "enhance" in the passage (paragraph 3) is closest in meaning toA.control.B.limit.bine.D.increase.7.Which of the following best explains the process of permineralization mentioned in paragraph 3?A.Water containing calcium carbonate circulates through a shell and deposits sediment.B.Liquid containing chemicals hardens an already existing fossil structure.C.Water passes through sediment surrounding a fossil and removes its chemical content.D.A chemical substance enters a fossil and changes its shape.8.The word "precise" in the passage (paragraph 4) is closest in meaning toplex.B.quick.C.exact.D.reliable.9.Paragraph 5 suggests which of the following about the carbonization process?A.It is completed soon after an organism dies.B.It does not occur in hard-shell organisms.C.It sometimes allows soft-tissued organisms to bepreserved with all their parts.D.It is a more precise process of preservation than is replacement.10.The word "prospect" in the passage (paragraph 6) is closest in meaning topletion.B.variety.C.possibility.D.speed.11.According to paragraph 7, how do environments containing oxygen affect fossil preservation?A.They increase the probability that soft-tissued organisms will become fossils.B.They lead to more bacteria production.C.They slow the rate at which clay and silt are deposited.D.They reduce the chance that animal remains will be preserved.12.According to paragraph 7, all of the following assist in fossil preservation EXCEPTA.the presence of calcite in an organism's skeleton.B.the presence of large open areas along an ocean floor.C.the deposition of a fossil in sticky substances such as sap or tar.D.the rapid burial of an organism under layers of silt.13. Look at the four squares [■] that indicate where the following sentence can be added to the passage. Where would the sentence best fit? Click on a square [■] to insert the sentence in the passage. But the evidence of past organic life is not limited to petrifaction. ■【A】Another type of fossilization, known as carbonization, occurs when soft tissues are preserved as thinfilms of carbon. ■【B】Leaves and tissue of soft-bodied organisms such as jellyfish or worms may accumulate, become buried and compressed, and lose their vola tile constituents. ■【C】The carbon often remains behind as a blackened silhouette.■【D】14. Directions: An introductory sentence for a brief summary of the passage is provided below. Complete the summary by selecting the THREE answer choices that express the most important ideas in the passage. Some answer choices do not belong in the summary because they express ideas that are not presented in the passage or are minor ideas in the passage. This question is worth 2 points. The remains of ancient life are amazingly well preserved in the form of fossils.A.Environmental characteristics like those present on ocean floors increase the likelihood that plant and animal fossils will occur.B.Fossils are more likely to be preserved in shale deposits than in deposits of clay and silt.C.The shells of organisms can be preserved by processes of chemical precipitation or mineral exchange.D.Freezing enables the soft parts of organisms to survive longer than the hard parts.paratively few fossils are found in the terrestrial deposits of streams and lakes.F.Thin films of carbon may remain as an indication of soft tissue or actual tissue may be preserved if exposure to bacteria is limited.托福阅读答案1.agency代理,中介,作用,所以答案是force,选C。
Unit 1 Translation.1."材料科学〞涉与到研究材料的结构与性能的关系.相反,材料工程是根据材料的结构与性质的关系来涉与或操控材料的结构以求制造出一系列可预定的性质.2.实际上,所有固体材料的重要性质可以分为六类:机械、电学、热学、磁学、光学、腐蚀性.3.除了结构与性质,材料科学与工程还有其他两个重要的组成部分,即加工与性能.4.工程师或科学家越熟悉材料的各种性质、结构、性能之间的关系以与材料的加工技术,根据以上的原则,他或她就会越自信与熟练地对材料进行更明智的选择.5.只有在少数情况下,材料才具有最优或最理想的综合性质.因此,有时候有必要为某一性质而牺牲另一性能.6.Interdisciplinary dielectric constantSolid material<s> heat capacityMechanical property electromagnetic radiationMaterial processing elastic modulus7.It was not until relatively recent times that scientists came to understand the relationships between the structural elements of materials and their properties.8. Materials engineering is to solve the problem during the manufacturing and application of materials.9.10.Mechanical properties relate deformation to an applied load or force.Unit 21.金属是电和热很好的导体,在可见光下不透明;擦亮的金属表面有金属光泽.2.陶瓷是典型的导热导电的绝缘体,并且比金属和聚合物具有更高的耐热温度和耐恶劣环境性能.3.用于高科技领域的材料有时也被称为先进材料.4.压电陶瓷在电场作用下膨胀和收缩;反之,当它们膨胀和收缩时,他们也能产生一个电场.5.随着能够观察单个原子或者分子的扫描探针显微镜的出现,操控和移动原子和分子以形成新结构成为可能,因此,我们能通过一些简单的原子水平的构建就可以设计出新的材料.6.advanced materials ceramic materialshigh-performance materials clay mineralsalloy implantglass fibre carbon nanotube7.Metallic materials have large numbers of nonlocalized electrons and many properties of metals are directlyattributable to these electrons.8.Many of polymeric materials are organic compounds with very large molecular structures.9.Semiconductors hace electrical properties that are intermediate between the electrical conductors<viz. metalsand metal alloys> and insulators<viz. ceramics and polymers>.10.Biomaterials must not produce toxic substances and must be compatible with body tissues.Unit 31.金属的行为〔性质〕不同于陶瓷的行为〔性质〕,陶瓷的行为〔性质〕不同于聚合物的行为〔性质〕. 2.原子结构主要影响化学性质、物理性质、热学性质、电学性能、磁性能、光学性能.微结构和宏观结构虽也能影响这些性能但是他们主要影响力学性能和化学反应速率.3.金属的强度表明原子是通过强的键结合在一起的.4.元素的原子序数表明该元素的原子核内带正电的质子数.而原子的原子量则表明该原子核中质子数与中子数.5.Microstructure macrostructureChemical reaction atomic weightBalanced electrical charge positively charged proton6. 100 atoms form thousands of different substances ranging from the air we breathe to the metal used to supporttall buildings,7.The facts suggests that metallic atoms are held together bu strong bonds.8. Microstructure which includes features that cannot be seen with the naked eye,but using a microscope.Macrostructure includes features that can be seen with the naked eye.9. The atomic weight is the sum of proton number and neutron number in the nucleus.Unit 41.当密度小于水的密度时,物体将漂浮在水面上,当密度大于水的密度时,物体会沉降.相似的,当比重小于1时,物体将漂浮在水面上,当比重大于1时,物体会沉降.2.由于相互排斥而往相反的方向移动,导致磁通量密度比真空中小,这种材料为反磁性材料.3.使磁通量密度提高1倍以上小于或等于10倍的材料叫顺磁性材料,使磁通量密度提高10倍以上的材料叫铁磁性材料.4.某些铁磁性材料,特别是一些粉末状或夹层铁,钢或镍合金的相对导磁率可高达1000000.反磁性材料的相对导磁率小于1,但是到目前还没有哪种材料的相对导磁率远小于1.5.当顺磁性或铁磁性的芯插入线圈时,其磁感应系数等于相对磁导率乘以空芯时的磁感应系数. 6.specific gravity boiling point magnetic inductioncoefficient of thermal conductivity glass transition temperaturenon-ferrous metals linear coefficient of thermal expansionmass per unit of volume7. Properties that describe how a substance changes into a completely different substance are called chemicalproperties.8. Phase is a physical property of matter and matter can exist in four phases: solid, liquid, gas and plasma.9. At some temperature below the melting point, polymers start to lose their crystalline structure but the moleculesremain linked in chains, which tesults in a soft and pliable material.10. In engineering applications, permeability is often expressed in relative, rather than in absolute.Unit 51. 金属的力学性能决定了材料的使用X围与期望的服役寿命.2. 因此,一般多测几次以得到力学性能,报导的数值一般是平均值或者计算的统计最小值.3.材料的承载方式极大地影响了材料的力学性能,也决定了材料失效形式,以与在失效前是否有预警. 4.然而,受力弯曲时会产生一个应力分布,应力大小与到轴线的垂直距离有关.5.材料受到低于临界压力即屈服强度的力时,材料才会发生弹性形变.6.Test specimen static loading force normal axisEngineering strain critical stress yield strength stress areaStress- strain curve7. Temperatures below room temperature generally cause an increase in strength properties of metallic alloys;while ductility, fracture toughness, and elongation usually decrease.8. From the respective of what is happening within a material, stress is the internal distribution of forces withina body that balance and react to the loads applied to it.9. Engineering strain is defined as the amount of deformation in the direction of the applied force divided bythe initial length of the material.10. A material with high strength and high ductility will hace more toughness than a material with low strengthand high ductility.Unit 61. 随着影响我们星球上人类生存条件的社会问题的即将出现,材料科学与工程界有责任和机遇通过解决未来世界的需求—在能量、交通、住房、饮食、回收和健康方面的需求来改变世界.2. 不发达国家的人口增长率远高于1.4%的世界平均人口增长率.3. 全球能源使用的预算在2025以前将以每年1.7%速度增长,这比世界人口增长率快多了.4. 此外,发达地区的人均能量使用量是不发达地区人均能量使用量的九倍以上.5. gross domestic product materials science and engineering market economySocietal issues economic index sanitationGross national product popilation growth rate6. Some things that have been constant over time are human innovation and creativity, the engineer’s ability toaddress societal needs, and the entrepreneurial spirit of engineering.7. We have witnessed the re-shaping of our lives through revolutions that hace taken place in medicine,telecommunications, and transportantion industries.8. Eighteen percent of the world’s population lacks access to safe drinking water and nearly 40% has no access tosanitation.9. Materials and society are interlinked, and it is only rational that we should see a close relation between the MSEresearch agenda and societal issues that affect the human condition on the globe.Unit 71.从化学角度来说,金属是一类容易失电子以形成正离子的元素,它与其他金属原子形成金属键.2.金属键的无方向性被认为是金属具有延展性的主要原因.3.存在着共价键的晶体只有在原子之间的键断裂的情况下变形,从而导致晶体破裂.4.合金特别是为满足更高应用要求的合金比如喷气发动机,可能含有十种以上的元素.5.delocalized electron electronic structurealkaline earth metal chemical cellnuclear charge electric conductivity6.Metals are sometimes described as a lattice of positive ions surrounded by a cloud of delocalized electrons.7.Metals in general have superior electric and thermal conductivity, high luster and density, and the ability to bedeformed under stress without cleaving.8.An alloy is a mixture of two or more elements in solid solution in which the major component is a metal.bining different ration of metals as alloys modifies the properties of pure metals to produce desirablecharacteristics.Unit 81.超耐热合金的发展非常依赖于化学与加工的创新,并主要受到航空和能源工业的推动.2.抗蠕变性能主要取决于晶体结构内位错速度的放缓.3.超耐热合金在加工方面的发展使超耐热合金的操作温度大幅度提高.4.单晶高温合金是运用改进的定向凝固技术而形成单晶的,因此在材料中并无晶界.5.faced-centred cubic crystal structure turbine entry temperaturemetallic materials phase stabilitynuclear reactor synthesis of nanoparticle6.Superalloys typically hace an sustenitic faced-centered cubic crystal structure.7.Superalloys are used where there is a need for high temperature strength and corrosion/oxidation resistance.8.Superalloys are widely used in aircraft ,submarines, nuclear reactors and military electric motors.9.At high temperatures the gaseous aluminum chloride<or fluoride> is transfereed to the surface of part anddiffuseds inside.Unit 91.腐蚀过程从本质上说是一个电化学的过程,有着与电池相同的本质特征.2. 从矿物中提炼金属所需能源的问题与后续的腐蚀和能量释放直接相关.3. 当电子与中和的正离子〔如电解液中的氢离子〕发生反应时,阴极处电子得以平衡.4.Protective film circuitFree electron electron transferMetal cation anode reaction5.Some metals, such as gold and silver, can be found in the earth in their natural, metallic state, and they havelittle tendency to corrode.6.Oxidation is the process of stripping electrons from an atom and reduction occurs when an electron is addedto an atom.7.If the surface becomes wet, corrosion may take place through ionic exchange in the surface water layerbetween the anode and cathode.8.Corrosion is commonly classification based on the appearance of the corroded material.Unit 101. 我们要观察〔研究〕这些性能,看它们与我们所期望的陶瓷的组成有多匹配.2. 在高于玻璃化转变温度的高温下,玻璃不再具有脆性行为,而表现为粘稠液体.3. 它们显示出优异的力学性能、抗腐蚀/氧化性能,或电学、光学抑或是磁学性能.4. 一般认为,先进是最近100年才发展起来的,而传统的基于粘土的陶瓷早已在25000多年前就被使用了.5. the glass transition temperature ionic-covalent bondStress distribution coefficient of thermal expansionGlass optical fibre materials science and engineeringSolid-oxide fuel cells electron microscopy6. Diamond, which is classified as a ceramic, has the highest thermal conductivity of any known material.7. Ceramic are stronger in compression than in tension, whereas metals have comparable tensile and compressivestrength.8. Ceramics generally have low toughness, although combining them in composites can dramatically improvethis property.9. The functions of ceramic products are dependent on their chemical composition and microstructure, whichdetermines their properties.Unit 111. 材料科学与工程领域经常是根据四大方面—合成与加工,结构与组成,性质与性能之间的相互联系来定义的.2.我们不仅要考虑具有完美晶格和理想结构〔的情况〕,我们也要考虑材料中不可避免的结构缺陷的存在,甚至是无定形的.3. 通过热压可使孔径减小从而得到高密度产品.4. 在运输时,厂方要提供关于产品危害方面的信息.5. crystalline ceramics grain boundaryAlkaline earth oxide oxide additiveTriple point saturation magnetizationTelevision tube the color scale6.To understand the behavior and properties of any material, it is essential to understand its structure.7.The grain size is determined by the size of the initial powder particles and the way in which they wereconsolidated.8.Transparent or translucent ceramics require that we limit the scattering of light by pores and second-phaseparticles.9.Alumina ceramics are used as electrical insulators because of theie high electrical resistivity and lowdielectric constant.Unit 121. 材料的选择是任何组分设计至关重要的环节,尤其在植入体和其它医疗器械方面是特别重要的.2. 我们能进行承载应用的三种主要材料是金属、聚合物和陶瓷.3. 高密度、高纯度的氧化铝被大量的用于植入物,特别是在需要承载压力的髋关节修复和牙移植中.4. 在陶瓷或陶瓷复合材料中,氧化锆的磨损率远远高于氧化锆铝的磨损率.5. controlled reaction stress shieldingTotal hip prosthese strain-to-failure ratioMechanical stress flexural strengthMartensitic transformation6.Biomaterial is a non-viable material used in a medical device intended to interact with biological systems.7.These repairs become necessary when the existing part becomes diseased, damaged, or just simply wears out.8.Because of its low density, cancellous bone has a lower E and higher strain-to-failure ratio than cortical bone.9.Eliminating stress shielding, by reducing E, is one of the primary motivations for the development ofbioceramic composites.10.There are questions concerning the long-term effect of radiation emission from zirconia ceramics.Unit 131. 聚合物的俗名叫塑料,这个词指的是一大类具有许多性质和用途的天然材料和合成材料.2. 聚合物合成是一个把叫做单体的小分子通过共价键的结合形成链的过程.3. 支化聚合物分子是由一条带有一个或多个侧基或支链的主链组成.一些特殊的支化聚合物有星型聚合物、梳状聚合物和刷状聚合物.4. 某些生物聚合物是由一系列不同的胆识结构却相关的单体组成的,例如聚核苷酸是由核苷组成的.5. persistence length cross-linkPolar monomer nucleic acidPolymerization polyelectrolyte6.Most commercially important polymers today are entirely synthetic and produced in high volume, onappropriately scaled organic synthetic techniques.7.Some biological polymers are composed of a variety of different but structurally related monomers, suchas polynucleotides composed of nucleotide sbunits.8. A polymer molecule with a high degree of crosslinking is referred to as a polymer network.9.In polymers, however, the molecular mass may be expressed in terms of degree of polymerization,essentially the number of monomer Units which comprise the polymer.Unit 141. 大量合成的聚合物具有碳-碳骨架,这是因为碳原子具有与其它原子形成更强更稳定的键的优异性能.2. 它们在一定X围内软化,这与完好晶体相具有非常明确的熔点不同.3. 分子量取决于其合成时的条件,因此分子量可能分布很宽或分布很窄.4. Goodyear 很偶然的发现了在橡胶中加入硫磺并加热这个混合物能使橡胶变硬,对氧化和化学进攻能力的敏感性降低.5. thermosetting plastic cross-sectional areaPolymerization reaction double bondChemical composition carboxylic acidMelting point degradation by oxidation6.Polymer with different chemical composition has different physical and chemical property.7. A thermosetting plastic is shaped through irreversible chemical processes and therefore cannot be reshapedreadily.8.Natural rubber is not a useful polymer because it is too soft and too chemically reactive.9.Various substances may be added to polymers to provide protection against the effects of sunlight or againstdegradation by oxidation.Unit 151. 逐渐增强的环境意识促使包装薄膜与其加工既要方便使用又要具有环境友好的特点.2. 显而易见,实现这些性能对控制和改进机械性能和阻隔性能是非常重要的.3. 在羧酸、醇、醛、酮的含氧生物降解过程中,由水和热引发的过氧化反应可以使之降解成低摩尔质量的物质,这就是碳氢聚合物力学性能降低的主要原因.4. 用持久耐用的聚合物做短期使用的包装材料并不合理,另外也是因为包装材料被食物污染后再进行物理回收是不切合实际的.5. natural gas packaging materialsAroma compound bioplastic materialChemical structure the life cycle of biomass6. Bacteria , fungi, enzymes start the bioassimilation giving rise to biomass and CO2 that finally form the humus.7. The bioplastic aim is to imitate the life cycle of biomass, which includes conservation of fossil resources, waterand CO2 production.8. During the oxo-degradation of carboxylic acid, molecules of alcohols, aldehydes and ketones degradable withlow molar mass are produced by peroxidation initiated by heat or light .9. While most of the commercialized biopolymer materials are biodegradable, these are not fully compostable inreal composting conditions, which vary with temperature and relative humidity.Unit 161. 比如,多相金属在微观尺度上是复合材料.但一般意义上的复合材料是指通过键的作用使两种或多种不同的材料结合在一起的材料..2. 最常见的是,复合材料有一个连续的叫基体的本体相,还有一个分散的非连续的叫增强相的相.3. 先进材料采用了树脂与纤维的复合材料,一般为碳/石墨,凯芙拉或玻璃纤维与环氧树脂的复合材料.纤维具有高的硬度,而聚合物树脂基体能保持复合材料的结构.4. 如果复合材料设计和制备合理的话,复合材料就既具有增强相的强度又具有基体的韧性从而得到了性能的理想组合,这是任何一种组分单独存在时所具备的性能.5. composite material reinforcement materialFiberglass matrix materialStrengthening mechanism conventional material6. A composite is commonly defined as a combination of two or more distinct materials, each of which retainsits own distinctive properties, to create a new material with properties that cannot be achieved by any of the components acting alone.7.Carbon-epoxy composties are two thirds the weight of aluminum, and two and a half times as stiff.Composites are resistant to fatigue damage and harsh enviroments, and are repairable.8.According to the conception of composite , reinforced plastics, metal-matrix composites, ceramic-matrixcomposites and concrete are composites.9.In fiber-reinforced composites, the fiber is the primary load-bearing component. Fiberglass and carbon fibercomposites are examples of fiber-reinforced composites.Unit 171. 震荡、撞击或者重复的周期性应力能导致两层的界面处发生薄层分离,这种情况叫剥离.2.3. 事实上,工业材料既要质轻又要牢固的要求是推动复合材料发展的主要动力.4. 提到飞机,值得铭记的是复合材料不像金属〔如铝〕那样在压力的作用下会完全解体.5. orthotropic thermosetThermoplastic Young’s ModulusMechanical property constants extreme enviroment6.In contrast, isotropic material < for example, aluminuim or steel>, in standard wrought forms, typicallyhave the same stiffness regardless of the directional orientation of the applied forces and /or moments.7.The greatest advantage of composite materials is strength and stiffness combined with lightness.8.This makes them ideal for use in products thar are exposed to extreme enviroments such as boats,chemical-handling equipments and spacecrafts.posites will never totally replace tranditional materials like steel, but in many cased they are just whatwe need.Unit 181. 具有相分离的聚合物共混材料经常出现纳米尺度的相.2 在过去几十年里研究的基于溶胶-凝胶化学的有机-无机纳米复合材料已基本淡出纳米复合材料的研究.3. 理解粒子的性质随着尺寸降低到纳米级别而发生改变,这对于优化所得到的纳米复合材料很重要.4. 廉价石墨的生产尚未实现,石墨的广泛使用呕待石墨合成技术的突破.5. electro-optical property bactericidal propertyBlock copolymer interfacial phenomenaExfoliated graphene morphology control6.The field of nanotechnology is one of the most popular areas for current research and development inbasically all technical discillines.7.Nanoscale is considered where the dimensions of the particle, platelet or fiber modification are in the rangeof 1~100nm.8.These improvements are key to future aircraft and wind energy turbine applications.9.Nanostructured surfaces have been noted to yield superhydrophobic character and exceptional adhesion.。
材料专业英语常见词汇The saying "the more diligent, the more luckier you are" really should be my charm in2006.材料专业英语常见词汇一Structure 组织Ceramic 陶瓷Ductility 塑性Stiffness 刚度Grain 晶粒Phase 相Unit cell 单胞Bravais lattice 布拉菲点阵Stack 堆垛Crystal 晶体Metallic crystal structure 金属性晶体点阵 Non-directional 无方向性Face-centered cubic 面心立方Body-centered cubic体心立方 Hexagonal close-packed 密排六方 Copper 铜Aluminum 铝Chromium 铬 Tungsten 钨Crystallographic Plane晶面 Crystallographic direction 晶向 Property性质 Miller indices米勒指数 Lattice parameters 点阵参数Tetragonal 四方的Hexagonal 六方的Orthorhombic 正交的Rhombohedra 菱方的Monoclinic 单斜的Prism 棱镜 Cadmium 镉 Coordinate system 坐 Point defec点缺陷Lattice 点阵 Vacancy 空位Solidification 结晶Interstitial 间隙Substitution 置换Solid solution strengthening 固溶强化Diffusion 扩散Homogeneous 均匀的Diffusion Mechanisms 扩散机制Lattice distortion 点阵畸变Self-diffusion 自扩散Fick’s First Law 菲克第一定律 Unit time 单位时间Coefficient 系数Concentration gradient 浓度梯度Dislocations 位错Linear defect 线缺陷Screw dislocation 螺型位错Edge dislocation 刃型位错Vector 矢量Loop 环路Burgers’vector 柏氏矢量Perpendicular 垂直于Surface defect 面缺陷Grain boundary 晶界Twin boundary 晶界 Shear force 剪应力Deformation 变形Small or low angel grain boundary 小角度晶界Tilt boundary 倾斜晶界Supercooled 过冷的Solidification 凝固Ordering process 有序化过程Crystallinity 结晶度Microstructure 纤维组织Term 术语Phase Diagram 相图Equilibrium 平衡Melt 熔化Cast 浇注Crystallization 结晶Binary Isomorphous Systems 二元匀晶相图Soluble 溶解Phase Present 存在相Locate 确定Tie line 连接线Isotherm 等温线Concentration 浓度Intersection 交点The Lever Law 杠杆定律Binary Eutectic System 二元共晶相图Solvus Line 溶解线Invariant 恒定Isotherm 恒温线Cast Iron 铸铁Ferrite 珠光体Polymorphic transformation 多晶体转变Austenite 奥氏体Revert 回复Intermediate compound 中间化合物Cementite 渗碳体Vertical 垂线Nonmagnetic 无磁性的Solubility 溶解度Brittle 易脆的Eutectic 共晶Eutectoid invariant point 共析点Phase transformation 相变Allotropic 同素异形体Recrystallization 再结晶Metastable 亚稳的Martensitic transformation 马氏体转变Lamellae 薄片Simultaneously 同时存在Pearlite 珠光体Ductile 可塑的Mechanically 机械性能Hypo eutectoid 过共析的Particle 颗粒Matrix基体Proeutectoid 先共析Hypereutectoid 亚共析的Bainite 贝氏体Martensite 马氏体Linearity 线性的Stress-strain curve 应力-应变曲线Proportional limit 比例极限Tensile strength 抗拉强度Ductility 延展性Percent reduction in area 断面收缩率Hardness 硬度Modulus of Elasticity 弹性模量Tolerance 公差Rub 摩擦Wear 磨损Corrosion resistance 抗腐蚀性Aluminum 铝Zinc 锌Iron ore 铁矿Blast furnace 高炉Coke 焦炭Limestone 石灰石Slag 熔渣Pig iron 生铁Ladle 钢水包Silicon 硅Sulphur 硫Wrought 可锻的Graphite 石墨Flaky 片状Low-carbon steels 低碳钢Case hardening 表面硬化Medium-carbon steels 中碳钢Electrode 电极As a rule 通常Preheating 预热Quench 淬火Body-centered lattice 体心晶格Carbide 碳化物Hypereutectoid过共晶Chromium 铬Manganese 锰Molybdenum 钼Titanium 钛Cobalt 钴Tungsten 钨Vanadium 钒Pearlitic microstructure 珠光体组织Martensitic microstructure 马氏体组织Viscosity 粘性Wrought 锻造的Magnesium 镁Flake 片状Malleable 可锻的Nodular 球状Spheroidal 球状Superior property 优越性Galvanization 镀锌Versatile 通用的Battery grid 电极板Calcium 钙Tin 锡Toxicity 毒性Refractory 耐火的Platinum铂Polymer 聚合物Composite 混合物Erosive 腐蚀性Inert 惰性Thermo chemically 热化学Generator 发电机Flaw 缺陷Variability 易变的Annealing 退火Tempering回火Texture 织构Kinetic 动力学Peculiarity 特性Critical point 临界点Dispersity 弥散程度Spontaneous 自发的Inherent grain 本质晶粒Toughness 韧性Rupture 断裂Kinetic curve of transformation 转变动力学曲线Incubation period 孕育期Sorbite 索氏体Troostite 屈氏体Disperse 弥散的Granular 颗粒状Metallurgical 冶金学的Precipitation 析出Depletion 减少Quasi-eutectoid 伪共析Superposition 重叠Supersede 代替Dilatometric 膨胀Unstable 不稳定Supersaturate 使过饱和Tetragonality 正方度Shear 切变Displacement 位移Irreversible 不可逆的金属材料工程专业英语acid-base equilibrium酸碱平衡 acid-base indicator酸碱指示剂 acid bath酸槽 acidBessemerconverter 酸性转炉 acid brick酸性耐火砖 acid brittleness酸洗脆性、氢脆性 acid burden酸性炉料acid clay酸性粘土 acid cleaning同pickling酸洗 acid concentration酸浓度 acid converter酸性转炉 acid converter steel酸性转炉钢 acid content酸含量 acid corrosion酸腐蚀 acid deficient弱酸的、酸不足的 acid dip酸浸acid dip pickler沉浸式酸洗装置 aciddiptank酸液浸洗槽acid drain tank排酸槽acidless descaling无酸除鳞acid medium酸性介质acid mist酸雾acid-proof paint耐酸涂料漆acid-proof steel耐酸钢acid-resistant耐酸钢acid-resisting vessel耐酸槽acid strength酸浓度acid supply pump供酸泵acid wash酸洗acid value酸值acid wash solution酸洗液acieration渗碳、增碳Acm point Acm转变点渗碳体析出温度acorn nut螺母、螺帽acoustic absorption coefficient声吸收系数acoustic susceptance声纳actifier再生器action line作用线action spot作用点activated atom激活原子activated bath活化槽activated carbon活性碳activating treatment活化处理active corrosion活性腐蚀、强烈腐蚀active area有效面积active power有功功率、有效功率active product放射性产物active resistance有效电阻、纯电阻active roll gap轧辊的有效或工作开口度active state活性状态active surface有效表面activity coefficient激活系数、活度系数actual diameter钢丝绳实际直径actual efficiency实际效率actual error实际误差actual time实时actual working stress实际加工应力actuating device调节装置、传动装置、起动装置actuating lever驱动杆、起动杆actuating mechanism 动作机构、执行机构actuating motor驱动电动机、伺服电动机actuating pressure作用压力actuation shaft起动轴actuator调节器、传动装置、执行机构acute angle锐角adaptive feed back control自适应反馈控制adaptive optimization自适应最优化adaptor接头、接合器、连结装置、转接器、附件材料科学基础专业词汇:第一章晶体结构原子质量单位 Atomic mass unit amu 原子数 Atomic number 原子量 Atomic weight波尔原子模型 Bohr atomic model 键能 Bonding energy 库仑力 Coulombic force共价键 Covalent bond 分子的构型 molecular configuration电子构型electronic configuration 负电的 Electronegative 正电的 Electropositive基态 Ground state 氢键 Hydrogen bond 离子键 Ionic bond 同位素 Isotope金属键 Metallic bond 摩尔 Mole 分子 Molecule 泡利不相容原理 Pauli exclusion principle 元素周期表 Periodic table 原子 atom 分子 molecule 分子量 molecule weight极性分子 Polar molecule 量子数 quantum number 价电子 valence electron范德华键 van der waals bond 电子轨道 electron orbitals 点群 point group对称要素 symmetry elements 各向异性 anisotropy 原子堆积因数 atomic packing factorAPF 体心立方结构 body-centered cubic BCC 面心立方结构 face-centered cubic FCC布拉格定律bragg’s law 配位数 coordination number 晶体结构 crystal structure晶系 crystal system 晶体的 crystalline 衍射 diffraction 中子衍射 neutron diffraction电子衍射 electron diffraction 晶界 grain boundary 六方密堆积 hexagonal close-packed HCP 鲍林规则 Paulin g’s rules NaCl型结构 NaCl-type structureCsCl型结构Caesium Chloride structure 闪锌矿型结构 Blende-type structure纤锌矿型结构 Wurtzite structure 金红石型结构 Rutile structure萤石型结构 Fluorite structure 钙钛矿型结构 Perovskite-type structure尖晶石型结构 Spinel-type structure 硅酸盐结构 Structure of silicates岛状结构 Island structure 链状结构 Chain structure 层状结构 Layer structure架状结构 Framework structure 滑石 talc 叶蜡石 pyrophyllite 高岭石 kaolinite石英 quartz 长石 feldspar 美橄榄石 forsterite 各向同性的 isotropic各向异性的 anisotropy 晶格 lattice 晶格参数 lattice parameters 密勒指数 miller indices 非结晶的 noncrystalline多晶的 polycrystalline 多晶形 polymorphism 单晶single crystal 晶胞 unit cell电位 electron states化合价 valence 电子 electrons 共价键 covalent bonding金属键 metallic bonding 离子键Ionic bonding 极性分子 polar molecules原子面密度 atomic planar density 衍射角 diffraction angle 合金 alloy粒度,晶粒大小 grain size 显微结构 microstructure 显微照相 photomicrograph扫描电子显微镜 scanning electron microscope SEM透射电子显微镜 transmission electron microscope TEM 重量百分数 weight percent四方的 tetragonal 单斜的monoclinic 配位数 coordination number材料科学基础专业词汇:第二章晶体结构缺陷缺陷 defect, imperfection 点缺陷 point defect 线缺陷 line defect, dislocation面缺陷 interface defect 体缺陷 volume defect 位错排列 dislocation arrangement位错线 dislocation line 刃位错 edge dislocation 螺位错 screw dislocation混合位错 mixed dislocation 晶界 grain boundaries 大角度晶界 high-angle grain boundaries 小角度晶界 tilt boundary, 孪晶界 twin boundaries 位错阵列 dislocation array位错气团 dislocation atmosphere 位错轴dislocation axis 位错胞 dislocation cell位错爬移 dislocation climb 位错聚结 dislocation coalescence 位错滑移 dislocation slip位错核心能量 dislocation core energy 位错裂纹 dislocation crack位错阻尼 dislocation damping 位错密度 dislocation density原子错位 substitution of a wrong atom 间隙原子 interstitial atom晶格空位 vacant lattice sites 间隙位置 interstitial sites 杂质 impurities弗伦克尔缺陷 Frenkel disorder 肖脱基缺陷 Schottky disorder 主晶相 the host lattice错位原子 misplaced atoms 缔合中心 Associated Centers. 自由电子 Free Electrons电子空穴Electron Holes 伯格斯矢量 Burgers 克罗各-明克符号 Kroger Vink notation中性原子 neutral atom材料科学基础专业词汇:第二章晶体结构缺陷-固溶体固溶体 solid solution 固溶度 solid solubility 化合物 compound间隙固溶体 interstitial solid solution 置换固溶体 substitutional solid solution金属间化合物 intermetallics 不混溶固溶体 immiscible solid solution转熔型固溶体 peritectic solid solution 有序固溶体 ordered solid solution无序固溶体 disordered solid solution 固溶强化 solid solution strengthening取代型固溶体 Substitutional solid solutions 过饱和固溶体 supersaturated solid solution非化学计量化合物 Nonstoichiometric compound材料科学基础专业词汇:第三章熔体结构熔体结构 structure of melt过冷液体 supercooling melt 玻璃态 vitreous state软化温度 softening temperature 粘度 viscosity 表面张力 Surface tension介稳态过渡相 metastable phase 组织 constitution 淬火 quenching退火的 softened 玻璃分相 phase separation in glasses 体积收缩 volume shrinkage材料科学基础专业词汇:第四章固体的表面与界面表面 surface 界面 interface 同相界面 homophase boundary异相界面 heterophase boundary 晶界 grain boundary 表面能 surface energy小角度晶界 low angle grain boundary 大角度晶界 high angle grain boundary共格孪晶界 coherent twin boundary 晶界迁移 grain boundary migration错配度 mismatch 驰豫 relaxation 重构 reconstuction 表面吸附 surface adsorption表面能 surface energy 倾转晶界 titlt grain boundary 扭转晶界 twist grain boundary倒易密度 reciprocal density 共格界面 coherent boundary 半共格界面 semi-coherent boundary 非共格界面 noncoherent boundary 界面能 interfacial free energy应变能 strain energy 晶体学取向关系 crystallographic orientation惯习面habit plane材料科学基础专业词汇:第五章相图相图 phase diagrams 相 phase 组分 component 组元 compoonent相律 Phase rule 投影图 Projection drawing 浓度三角形 Concentration triangle冷却曲线 Cooling curve 成分 composition 自由度 freedom相平衡 phase equilibrium 化学势 chemical potential 热力学 thermodynamics相律 phase rule 吉布斯相律 Gibbs phase rule 自由能 free energy吉布斯自由能 Gibbs free energy 吉布斯混合能 Gibbs energy of mixing吉布斯熵 Gibbs entropy 吉布斯函数 Gibbs function 热力学函数 thermodynamics function 热分析 thermal analysis 过冷 supercooling 过冷度 degree of supercooling杠杆定律 lever rule 相界 phase boundary 相界线 phase boundary line相界交联 phase boundary crosslinking 共轭线 conjugate lines相界有限交联 phase boundary crosslinking 相界反应 phase boundary reaction相变 phase change 相组成 phase composition 共格相 phase-coherent金相相组织 phase constentuent 相衬 phase contrast 相衬显微镜 phase contrast microscope 相衬显微术 phase contrast microscopy 相分布 phase distribution相平衡常数 phase equilibrium constant 相平衡图 phase equilibrium diagram相变滞后 phase transition lag 相分离 phase segregation 相序 phase order相稳定性 phase stability 相态 phase state 相稳定区 phase stabile range相变温度 phase transition temperature 相变压力 phase transition pressure同质多晶转变 polymorphic transformation 同素异晶转变 allotropic transformation相平衡条件 phase equilibrium conditions 显微结构 microstructures 低共熔体 eutectoid不混溶性 immiscibility材料科学基础专业词汇:第六章扩散活化能 activation energy 扩散通量 diffusion flux 浓度梯度 concentration gradient菲克第一定律Fick’s first law 菲克第二定律Fick’s second law 相关因子 correlation factor 稳态扩散 steady state diffusion 非稳态扩散 nonsteady-state diffusion扩散系数 diffusion coefficient 跳动几率 jump frequency填隙机制 interstitalcy mechanism 晶界扩散 grain boundary diffusion短路扩散 short-circuit diffusion 上坡扩散 uphill diffusion 下坡扩散 Downhill diffusion互扩散系数 Mutual diffusion 渗碳剂 carburizing 浓度梯度 concentration gradient浓度分布曲线 concentration profile 扩散流量 diffusion flux 驱动力 driving force间隙扩散 interstitial diffusion 自扩散 self-diffusion 表面扩散 surface diffusion空位扩散 vacancy diffusion 扩散偶 diffusion couple 扩散方程 diffusion equation扩散机理 diffusion mechanism 扩散特性 diffusion property 无规行走 Random walk达肯方程 Dark equation 柯肯达尔效应 Kirkendall equation本征热缺陷 Intrinsic thermal defect 本征扩散系数 Intrinsic diffusion coefficient离子电导率 Ion-conductivity 空位机制 Vacancy concentration材料科学基础专业词汇:第七章相变过冷 supercooling 过冷度 degree of supercooling 晶核 nucleus 形核 nucleation形核功 nucleation energy 晶体长大 crystal growth 均匀形核 homogeneous nucleation非均匀形核 heterogeneous nucleation 形核率 nucleation rate 长大速率 growth rate热力学函数 thermodynamics function 临界晶核 critical nucleus临界晶核半径 critical nucleus radius 枝晶偏析 dendritic segregation局部平衡 localized equilibrium 平衡分配系数 equilibrium distributioncoefficient有效分配系数 effective distribution coefficient 成分过冷 constitutional supercooling引领领先相 leading phase 共晶组织 eutectic structure 层状共晶体 lamellar eutectic伪共晶 pseudoeutectic 离异共晶 divorsed eutectic 表面等轴晶区 chill zone柱状晶区 columnar zone 中心等轴晶区 equiaxed crystal zone定向凝固 unidirectional solidification 急冷技术 splatcooling 区域提纯 zone refining单晶提拉法 Czochralski method 晶界形核 boundary nucleation位错形核 dislocation nucleation 晶核长大 nuclei growth斯宾那多分解 spinodal decomposition 有序无序转变 disordered-order transition马氏体相变 martensite phase transformation 马氏体 martensite材料科学基础专业词汇:第八、九章固相反应和烧结固相反应 solid state reaction 烧结 sintering 烧成 fire 合金 alloy 再结晶 Recrystallization 二次再结晶 Secondary recrystallization 成核 nucleation 结晶 crystallization子晶,雏晶 matted crystal 耔晶取向 seed orientation 异质核化 heterogeneous nucleation均匀化热处理 homogenization heat treatment 铁碳合金 iron-carbon alloy渗碳体 cementite 铁素体 ferrite 奥氏体austenite 共晶反应 eutectic reaction 固溶处理 solution heat treatment。
孪晶建立方法To start with, the process of establishing twins crystals, also known as twinning, is a fascinating phenomenon in the field of crystallography. Twinning occurs when two or more crystals share a common lattice orientation and grow together, resulting in a distinct mirror-image relationship between them. This phenomenon can have a significant impact on the physical and optical properties of the crystals, making them highly sought after in various industries, such as jewelry making, electronics, and pharmaceuticals.首先,孪晶建立的过程,也称为孪晶,是晶体学领域中一种迷人的现象。
当两个或更多的晶体具有共同的晶格取向并一起生长时,就会出现孪晶,导致它们之间存在明显的镜像关系。
这种现象可以显著影响晶体的物理和光学性质,使它们在珠宝制作、电子和制药等各个行业中备受追捧。
From a scientific perspective, twinning occurs due to specific crystallographic orientations that result in symmetrical relationships between the crystals. This phenomenon can be induced by various factors, such as external stress during the crystal growth process or specific lattice arrangements that favor twinning. Understanding theunderlying mechanisms of twinning is crucial for controlling and manipulating the growth of twinned crystals for desired properties and applications. Scientists and researchers continue to study and explore the intricacies of twinning to unlock its full potential in material science and technology.从科学角度来看,孪晶是由于特定的晶体学取向而导致晶体之间存在对称关系。
翻译1.电极电位决定离子浓度Electrode potential depends on the concentration of the ions.2.探索矿物中汞浓度的绝对因素被发现The determination of trace concentrations of mercury in mineral is describe.3.由于目前高品质的矿石可能耗尽,富集过程是十分重要的A concentration process is important now that the depletion of high grade ores is possibility.4.用这种加工方法会浪费一些材料The machining of forgings by this method entails some loss of material.5.阿基米德最先发现固体排水的原理Archimedes first discovered the principle that water is displaced by solid bodies.6.火箭被发明应用于宇宙勘探Rocket have found application for the exploration of the universe.5.要特别注意软管,确保不被磨损Particular attention should be given to ensure that chafing does not occur.7.所有动植物的生长都需要碳All plant and animals need for growth.8.加热可以提高液体温度The temperature of the liquid is raised by the application of heat.9.夯锤由压缩空气驱动的可提高生产率Rammers driven by compressed air can increase the production rates.10.今天计算机广泛应用于解决数学问题,这些问题与天气预报和卫星送入轨道有关Today the electronic computer is widely used in solving mathematical problems having to do with weather forecasting and putting satellites into orbit.11.生产中少量产品时,数控机是极为有用的,录用生产零件必须资料的磁带可以存放起来,需要时还可重新使用和修改Numerical control machines are most useful when quantities of products to be produced are low or medium;the tape containing the information required to produce the part can be stored ,reused or modified when required.12.如果没有吸引力,电子会以直线方向飞离质子If there were no attraction,the electron would fly away from the proton in a straight line13.如果飞机速度降到一定水平以下就会突然失去升力A sudden loss lift will be experienced in case the aircraft speed falls below a certain level.14.假如油泵失灵,运转部件就会过热In case of an oil-pump failure,the moving parts will be overheat.15.万一有雾,飞机可以由指挥塔引导降落至跑道In the event of fog ,aircraft can be guided down to the runway from the control tower16.这部发动机可以高速运转,条件是把震动降低The engine can be run at very high speeds on condition the vibration can be damped out17.让水冷却十分钟再测温度Allow the water to cool for10minutes and the make the temperature.18不能行走的机器人能学会做工并孜孜不倦的工作,今天在世界各地的工厂里得到了使用Non-mobile robots,capable of learning to perform an industrial task and then of being left to perform it tirelessly,are even now in use in industrial plants all over the world.20.由于未能记住这些符号,使许多学生无法掌握他们选修的课程Failure to fix these symbols in mind keeps students from mastering the mathematical subject they take up.21假如速率或方向改变了,速度也会随之改变Velocity changes if either speed or the direction changes.22石油和天然气仍将是我们燃料的主要来源Oil and gas will continue to be our chief source of fuel23驱动这个机器的发动机是50马力的感应电动机The power unit for driving the machine is a 50-hp induction motor24一个物体的速度不会超过光速A material object can not have a speed greater than the speed of light.半导体器件,称为晶体管,在许多应用中是更换管Semiconductor device,called transistors,are replacing tubes in many applications严禁乱拆,以免损坏零件It is forbidden to dismantle it without permission so as to avoid any damage to its parts25.需要明确是磁力和电力是不同的It should be realized that magnetic forces and electric forces are not the same26 .除去水中的矿物质叫做软化The removal of minerals from water is called softening27.只有爱因斯坦的相对论能解释这种现象Einstein’s relativity theory is the only one which can explain such phenomena。
Colloids and Surfaces B:Biointerfaces17(2000)145–152Effect of binders on polymorphic transformation kinetics of carbamazepine in aqueous solutionMakoto Otsuka*,Tomoko Ohfusa,Yoshihisa Matsuda Department of Pharmaceutical Technology,Kobe Pharmaceutical Uni6ersity,Motoyama-Kitamachi4-19-1,Higashi-Nada,Kobe658,JapanReceived7June1999;accepted9July1999AbstractThe effects of binders on the polymorphic transformation kinetics of carbamazepine(CBZ)were investigated by thermal analysis and X-ray diffraction analysis.The binders used were hydroxypropylcellulose(HPC)(HPC-SL, molecular weight30000–50000;HPC-M,molecular weight50000–70000;HPC-L,molecular weight110000–150000).CBZ anhydrate form I and various concentrations of binder solutions were mixed at1000rpm and25°C. The amount of dihydrate transformed was evaluated based on the latent heat due to dehydration on DSC curves. Since thefirst-order plots for transformation process of CBZ showed a straight line,the transformation rate constant, k and induction period,IP were estimated based onfirst-order kinetics by the least-squares method.The k of CBZ decreased with increase of HPC-L concentration,but the IP increased.In contrast,the k of phase transformation on addition of crystal seeds was almost the same as that without seeds,but the IP significantly decreased on seed addition.The result suggested that IP was a nucleus formation process,but the seed addition did not affect the crystal growth process.The molecular weight effect of HPC on the transformation suggested that the k of HPC-SL was the largest,with the rank order being HPC-SL\HPC-M\HPC-L.The order for IP was HPC-L\HPC-SL\HPC-M. The relation between IP and kinematic viscosity had a straight line,but the k decreased with increase of kinematic viscosity.The increase of IP on addition of HPC might be induced by inhibition of the formation of nuclei by the steric intermolecular effect of HPC and decrease of D v.Therefore,HPC strongly inhibited nucleus formation in the crystallization of CBZ.©2000Elsevier Science B.V.All rights reserved.Keywords:Polymorphic transformation;Carbamazepine;Hydration;Nucleation;Crystal growth;Hydroxypropylcellulosewww.elsevier.nl/locate/colsurfb1.IntroductionHigh quality granular preparations offer a number of potential advantages to the pharma-ceutical industry in the production of beads or granules as bothfinished and intermediate prod-ucts.Therefore,various kinds of granulation tech-niques and equipment,such as extruders,fluidized beds and high speed mixers,have been developed to obtain high quality granular materials[1].Con-trolling these properties is an important factor in the production of high quality pharmaceuticals.*Corresponding author.Tel.:+81-78-441-7531;fax:+81-78-441-7532.E-mail address:m-otsuka@kobepharma-u.ac.jp(M.Otsuka)0927-7765/00/$-see front matter©2000Elsevier Science B.V.All rights reserved. PII:S0927-7765(99)00111-3M.Otsuka et al./Colloids and Surfaces B:Biointerfaces17(2000)145–152 146However,the pharmaceutical properties of gran-ules depend on various physical and chemical factors during manufacturing processes,such as instruments,formulations and manufacturing conditions.There is a few studies concerning to crystalline transformations during manufacturing process.The polymorphic form of an insoluble drug influences the bioavailability of preparations by affecting the dissolution rate[2].The physico-chemical stability related polymorphism affects the pharmaceutical properties,such as disintegra-tion time and mechanical strength of the prepara-tion[3].Carbamazepine(CBZ)is widely used as a potent anticonvulsant,and there have been re-ports concerning its polymorphic form[4–6]. CBZ polymorphic transformation at high humid-ity[7]and in aqueous suspension[8]was investi-gated and it was concluded that all forms transformed into the dihydrate.However,in a previous study[9],CBZ anhydrate form I was not transformed into dihydrate during CBZ granular formulation.This suggested that excipients,such as a binder,diluent and disintegrator,interacted with CBZ,and inhibited CBZ polymorphic trans-formation during granulation.In this study,there-fore,to clarify the interaction between excipients and CBZ,we investigated the effect of HPC as a binder on the polymorphic transformation of CBZ anhydrate.2.Materials and methods2.1.MaterialsCBZ bulk powder of Japanese Pharmacopoeia (JP)XIII grade(lot No.CEE-9-5)was obtained from Katsura Chem.Co.,Tokyo,Japan.The bulk powder was identified as being of polymor-phic form I[7]by X-ray diffraction analysis and DSC measurement.Hydroxypropylcellulose (HPC)(HPC-SL,molecular weight30000–50000;HPC-M,molecular weight50000–70000; HPC-L,molecular weight110000–150000;Ni-hon Soda Co.Japan)was used as a binder.All other chemicals were of analytical grade.2.2.Preparation of polymorphsThe CBZ bulk powder was identified as being of form I(anhydrate,monoclinic CBZ)[7].The dihydrate form(form IV)[7]was obtained by recrystallization as follows:the CBZ bulk powder was dissolved in50%ethanol solution in a water bath at70°C,andfiltered.After cooling the satu-rated CBZ solution to room temperature,the crystalline samples werefiltered and dried in a desiccator containing silica gel at room tempera-ture under vacuo for3h.All of the CBZ samples were passed through a no.200mesh(75m m) screen.2.3.Viscosity measurementThe kinematic viscosity was determined using a capillary viscometer at25°C(JP XIII).2.4.X-ray powder diffraction analysisDiffractograms were taken at room tempera-ture with an X-ray diffractometer(XD-3A,Shi-madzu Co.,Kyoto,Japan).The operating conditions were as follows:Target,Cu;filter,Ni; voltage20kV,current,20mA;receiving slit,0.1 mm;time constant,1s;counting range,1kcps; scanning speed4°2q min−1.2.5.Thermal analysisDifferential scanning calorimetry(DSC)was performed with a type3100instrument(Mac Sci-ence Co.,Tokyo).The operating conditions in the open-pan system were as follows:sample weight, 5mg;heating rate,10°C min−1;N2gasflow rate, 30ml min−1.2.6.Polymorphic transformation processA total of30g of CBZ bulk powder was mixed with200ml of0,0.001,0.005,0.05w/v%binder solution in a1000-ml round bottomedflask at a mixing speed of1000rpm at25°C.To evaluate the amount of dihydrate transformed5ml of suspension was sampled during mixing at5,10, 20,30,4560and85min,and afterfiltering theM .Otsuka et al ./Colloids and Surfaces B :Biointerfaces 17(2000)145–152147Fig.1.Powder X-ray diffraction profiles of CBZ forms.w /w%crystal content)in a mortar.The DSC curves of the standard samples were measured in triplicate.The standard deviation of the data was within 5%.The plots gave a good linear correla-tion and the linear regression equations were as follows:Y =308.4X +5.8(R =0.998)(1)where Y (J g −1)is a latent heat due to dehydra-tion of dihydrate CBZ.X is the dihydrate concen-tration (w /w%).R is the correlation coefficient.3.Results3.1.Effect of HPC -L concentration in binder solution on CBZ phase transformationFig.1shows the X-ray diffraction profiles of CBZ anhydrate,form I and dihydrate,form IV.The X-ray diffraction patterns of form I and dihydrate were significantly different and identical to those reported [6,7].Fig.2shows the effect of HPC-L concentration on the endothermic peak due to dehydration on DSC curves of CBZ dihy-drate.The endothermic peak of the samples in 0and 0.001%binder solution increased with mixing time,but not so in 0.05%solution.The X-ray diffraction profiles were consistent with this resultwet powders were stored at 30°C,47%RH for 24h to measure DSC.2.7.Measurement of the dihydrate contentThe dihydrate (form IV)content of the samples was measured by DSC based on the endothermic peak at around 70°C due to dehydration.Briefly,known quantities of standard mixtures were ob-tained by physically mixing anhydrate and dihy-drate at various ratios (0,25,50,75and 100Fig.2.Change of the DSC curves of CBZ forms during mixing (1000rpm)in binder solution at 25°C.M.Otsuka et al./Colloids and Surfaces B:Biointerfaces17(2000)145–152 148Fig.3.Effect of HPC-L concentration on hydration of CBZ form I. ,without additive; ,0.001%HPC-L; ,0.005% HPC-L; ,0.05%HPC-L.Fig.4.Effects of HPC-L concentration and the addition of seed crystals on thefirst-order plots for the hydration of CBZ form I. ,without additive; ,0.001%HPC-L; ,0.005% HPC-L; ,0.05%HPC-L; ,0.005%HPC-L with0.5% seeds.3.2.Effect of the molecular weight of the binder on CBZ phase transformationFig.5shows the effect of the molecular weight of HPC on CBZ phase transformation in aqueous suspension at25°C.The k and IP are summarized in Table1.The k of HPC-SL was the largest,with the rank order being HPC-SL\HPC-M\HPC-L.The(the data not shown).Thus,the CBZ anhydrate appeared to be transformed immediately to dihy-drate in aqueous suspension,but not in high binder solution.The amount of dihydrate transformed was evaluated based on the latent heat due to dehydration on DSC curves.Fig.3shows the effect of HPC-L concentration on the trans-formation of CBZ dihydrate.This suggested HPC-L inhibited the transformation of di-hydrate,and the effect depended on the concen-tration.Fig.4shows the effect of HPC-L on the first-order plots for polymorphic transformation of form I.Since the plot shows a straight line, the transformation rate constant,k and induction period,IP were estimated based onfirst-order kinetics by the least-squares method.The results are summarized in Table1.The k of CBZ de-creased with the increase of HPC-L concentra-tion,but the IP increased.In contrast,the k of phase transformation on the addition of crystal seeds was almost the same as that without seeds, but the IP significantly decreased on seed addi-tion.Table1Kinetic parameters for the transformation of CBZ aIP(min)k(min−1)Sample V(mm−2s−1)1.06×10−1 1.40 1.0000%binder0.001%HPC-L8.305.70×10−2 1.0060.005%HPC-L29.11.10×10−2 1.0261.04960.00.050%HPC-L02.63×10−226.70.005%HPC- 1.008SL0.005%HPC-14.76.10×10−3 1.018M1.0267.1431.41×10−20.005%HPC-L+seedsa k,transformation rate constant;IP,induction period;V, kinematic viscosity at25°C.M.Otsuka et al./Colloids and Surfaces B:Biointerfaces17(2000)145–152149 Fig.5.Effects of the molecular weight of HPC on thefirst-or-der plots for the hydration of CBZ form I. ,withoutadditive; ,0.005%HPC-SL; ,0.005%HPC-M; ,0.005%HPC-L.Fig.6.Effects of kinematic viscosity on the IP for hydration ofCBZ form I. ,without additive; ,HPC-L; ,HPC-M; ,HPC-SL.rank order for IP was HPC-L\HPC-SL\HPC-M.Since HPC-L has the highest molecular weight,the rank is HPC-L\HPC-M\HPC-SL, thus the k and IP were affected by the molecular weight of HPC.3.3.Effect of kinematic6iscosity on CBZ phase transformationFigs.6and7shows the effect of kinematic viscosity on the IP and k of CBZ transformation. The relation between IP and kinematic viscosity had a straight line,but that of k was a nonlinear and the k decreased with increase of kinematic viscosity.This suggested that the viscosity of the solution affected the crystal transformation kinet-ics of CBZ.4.Discussion4.1.Crystalline formation kineticsIn general,crystalline growth kinetics[11]con-sisted of nucleation and crystal growth and was controlled by various physical and chemical fac-tors.Eq.(4)shows nucleation velocity(J)based on Gibbs free energy change(D G)at constant temperature and pressure.The D G for formation of nuclei in radius r is expressed in Eq.(2),and dependent on D v and surface tension k.D G*is the formation of nuclei of clinical radius(r*) Fig.7.Effects of kinematic viscosity on the k for hydration of CBZ form I. ,without additive; ,HPC-L; ,HPC-M; , HPC-SL.M .Otsuka et al ./Colloids and Surfaces B :Biointerfaces 17(2000)145–152150Fig.8.Simulation curve of D G and J for the formation of nuclei upon crystallization based on Eqs.(3)and (4).The solid line and dotted lines represent D G and J ,respectively.The solubility is 10.ation,J ,increases with increase of D v ,the degree of supersaturation of solution,indicating that D v affects the D G and J of the crystallization process.Fig.9shows the effect of D v on the R max /J ratio of crystallization.The profile shows a maxi-mum peak at 1.3,and a decrease at values greater than D v =1.3(solubility =10).This suggests that the nucleation proceeds at higher D v ,but the crystal growth occurs at an D v of around 1.3after nucleation.Thus both nucleation and crystal growth proceed in more supersaturated solutions,but crystal growth occurs after nucleation at a lower degree of supersaturation.Young and Suryanarayanan [8]reported that CBZ anhydrate (form I)transformed into dihy-drate in aqueous solution following a first-order kinetics.In the present study,the crystalline trans-formation of CBZ anhydrate in aqueous solution also apparently followed first-order kinetics (Fig.4).However,the solid-to-solid transformation of CBZ during granulation is not simple crystalliza-tion,because it includes a starting material disso-lution process.In general,dissolution follows the Noiyes–Nernst Eq.(6).Kaneniwa et al.,[5]re-ported dissolution kinetics of CBZ form I based on the diffusion controlled dissolution model as shown in Eq.(6).−d C d t =DS wV l (C s−C )(6)D ,diffusivity of the drug;S w ,specific surface area;V ,volume of solution;t ,thickness of diffu-sion layer;C s ,solubility,C ,drug concentration at time t .obtained in Eq.(3).The J is affected through D G *by D v and k .D G (r )=4y r 33 D v +4y r 2k(2)D G*=4·4yk 3 23D v 2(3)J =4y r *2p q 1exp−D G*kT(4)where k ,surface energy; ,molecular volume;D v ,the degree of supersaturation of solution;s ,Boltzmann’s constant;m ,mass;r *,critical radius of nuclei;T ,absolute temperature;p ,concentra-tion of solution;q 1,density of critical nuclei at 0K.The crystal growth kinetics [11,12]is expressed as Wilson–Frenkel’s Eq.(5).Crystal growth rate,R max ,is also dependent on D v but independent of surface tension.R max = c 6aC e exp−D G dsl 8s T log(1+l )=D v(5)R max ,crystal growth rate; c ,molecular volume of crystal,a ,distance of crystal lattice;w ,vibration number of molecule;C e ,solubility of solution;D G ds ,Gibbs free energy of desolvation;|,degree of supersaturation;m ,mass.Fig.8shows the simulated results for nucle-ation based on Eqs.(3)and (4)at a constant temperature and pressure.The velocity of nucle-Fig.9.Simulation curve of D G /J for the formation of nuclei on crystallization based on Eqs.(3)and (4).The solubility is 10.M .Otsuka et al ./Colloids and Surfaces B :Biointerfaces 17(2000)145–152151Since there are several rate determination steps for crystalline transformation of CBZ,the crys-talline transformation in a suspension or during the kneading of wet mass for granulation consists of dissolution,nucleation and crystal growth as shown.Anhydrate Dissolutionk dSupersaturated solution Nucleationk nSS* Crystal growthk cDihydrate k d is the dissolution coefficient constant,k n is the nucleation rate constant and k c is the crystal growth rate constant.The SS*is activated super-saturated solution containing enough nuclei to start the crystal growth.Thus,the crystal trans-formation followed consecutive reaction kinetics,and included an induction period.4.2.Kinetic mechanism of inhibition of CBZ phase transformationIt is well known that polymer inhibits crystal growth in solution.Watanabe et al.[10]reported the inhibitory effect of sodium caseinate on the recrystallization of pheytoin from supersaturated solution.They concluded that the crystalline growth of phenytoin was inhibited by depression of the nuclei formation rate.On the other hand,the crystalline transformation of CBZ anhydrate apparently followed first-order kinetics,and was consistent with previous results.However,CBZ anhydrate in a formulation containing 0.05%HPC did not transform into dihydrate during granulation.Since the change of IP relative to viscosity was a linear (Fig.6),but that of k was non-linear (Fig.7),the mechanism of IP prolongation is not the same as that of depression of k .HPC might interact with CBZ,and inhibit crystallization of CBZ.On the other hand,the increase of viscosity on addition of HPC also might affect drug diffusion,D ,in dissolution (Eq.(6))and the activation energy of drug diffusion (D G ds )in crystal growth (Eq.(4)).This suggests that on increase of viscosity would induce a decrease of D v in the solution,and affect both the nucleation and crystal growth process.The results the effects of HPC con-centration (Fig.4)and molecular weight (Fig.5)effects are almost supported the theoretical hy-pothesis.The role of fine dihydrate crystals was investi-gated (see Fig.4).The k of 0.5%with seeds was almost the same as that without seeds,but the IP was significantly decreased by the seeds addition.The result suggested that IP was the nucleusformation process,but the seed addition is not affected by crystal growth.The increase of IP on addition of HPC (Fig.6)might be induced by inhibition of the formation of nuclei by the steric intermolecular effect of HPC and decrease of D v .Therefore,the addition of seed crystals did not affect the crystal growth rate.In other words,HPC strongly inhibited nucleus formation in the crystallization of CBZ.5.ConclusionsThe transformation of CBZ anhydrate was de-pressed dependent on the binder solution concen-tration.The transformation inhibition might be caused by the reduced of nucleus formation on HPC addition.The nature of the bulk powders and excipients,such as the polymorphic form,particle size and distribution,crystallinity etc.,reflect the history of the chemical and physical treatments of the raw materials.Since the phar-maceutical properties of the preparation are changed by the interaction between the formula-tions during the manufacturing process,the phar-maceutical properties could be controlled by regulating of the formula of the excipients.There-fore,to prepare better quality granules it is neces-sary to monitor and control the characteristics of the powder materials,such as bulk and excipient powders.AcknowledgementsThis work was supported in part by a Grant-in-Aid for Scientific Research from the Ministry of Education,Science and Culture,Japan.M.Otsuka et al./Colloids and Surfaces B:Biointerfaces17(2000)145–152 152References[1](a)M.Otsuka,J.Gao,Y.Matsuda,Effect of amount ofadded water during exrusion–spheronization process of pharmaceutical properties of granules,Drug Dev.Ind.Pharm.20(1994)2977–2992.(b)C.W.Woodruff,N.O.Nuessle,Effect of processing variable on particles ob-tained by extrusion–spheronization processing,J.Pharm.Sci.61(1972)787–790.(c)S.Watano,A.Yamamoto,K.Miyanami,Effect of operational variables on the proper-ties of granules prepared by moisture control method in tumblingfluidized bed 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物料科学Material Science 物料科学定义Material Science Definition加工性能Machinability强度Strength抗腐蚀及耐用Corrosion & resistance durability金属特性Special metallic features抗敏感及环境保护Allergic, re-cycling & environmental protection化学元素Chemical element元素的原子序数Atom of Elements原子及固体物质Atom and solid material原子的组成、大小、体积和单位图表The size, mass, charge of an atom, and is particles (Pronton,Nentron and Electron) 原子的组织图Atom Constitutes 周期表Periodic Table 原子键结Atom Bonding 金属与合金Metal and Alloy铁及非铁金属Ferrous & Non Ferrous Metal金属的特性Features of Metal 晶体结构Crystal Pattern 晶体结构,定向格子及单位晶格Crystal structure, Space lattice & Unit cell X线结晶分析法X – ray crystal analyics method 金属结晶格子Metal space lattice格子常数Lattice constant 米勒指数Mill's Index金相及相律Metal Phase and Phase Rule固熔体Solid solution 置换型固熔体Substitutional type solid solution 插入型固熔体Interstital solid solution金属间化物Intermetallic compound 金属变态Transformation 变态点Transformation Point磁性变态Magnetic Transformation同素变态Allotropic Transformation合金平衡状态Thermal Equilibrium 相律Phase Rule自由度Degree of freedom 临界温度Critical temperture共晶Eutectic 包晶温度Peritectic Temperature包晶反应Peritectic Reaction包晶合金Peritectic Alloy亚共晶体Hypoeutetic Alloy过共晶体Hyper-ectectic Alloy金属的相融、相融温度、晶体反应及合金在共晶合金、固熔孻共晶合金及偏晶反应的比较Equilibrium Comparision 金属塑性Plastic Deformation 滑动面Slip Plan畸变Distortion硬化Work Hardening退火Annealing回复柔软Crystal Recovery再结晶Recrystallization金属材料的性能及试验Properties & testing of metal 化学性能Chemical Properties物理性能Physical Properties颜色Colour磁性Magnetisum 比电阻Specific resistivity & specific resistance 比重Specific gravity & specific density比热Specific Heat热膨胀系数Coefficient of thermal expansion 导热度Heat conductivity 机械性能Mechanical properties屈服强度(降伏强度) (Yield strangth)弹性限度、阳氏弹性系数及屈服点elastic limit, Yeung's module of elasticity to yield point 伸长度Elongation 断面缩率Reduction of area金属材料的试验方法The Method of Metal inspection 不破坏检验Non – destructive inspections 渗透探伤法Penetrate inspection 磁粉探伤法Magnetic particle inspection放射线探伤法Radiographic inspection 超声波探伤法Ultrasonic inspection 显微观察法Microscopic inspection破坏的检验Destructive Inspection冲击测试Impact Test疲劳测试Fatigue Test潜变测试Creep Test潜变强度Creeps Strength 第壹潜变期Primary Creep第二潜变期Secondary Creep第三潜变期Tertiary Creep主要金属元素之物理性质Physical properties of major Metal Elements工业标准及规格–铁及非铁金属Industrial Standard – Ferrous & Non – ferrous Metal 磁力Magnetic简介General 软磁Soft Magnetic硬磁Hard Magnetic磁场Magnetic Field磁性感应Magnetic Induction透磁度Magnetic Permeability磁化率Magnetic Susceptibility (Xm) 磁力(Magnetic Force)及磁场(Magnetic Field)是因物料里的电子(Electron)活动而产生抗磁体、顺磁体、铁磁体、反铁磁体及亚铁磁体Diamagnetism, Paramagnetic, Ferromagnetism,Antiferromagnetism & Ferrimagnetism 抗磁体Diamagnetism磁偶极子Dipole负磁力效应Negative effect顺磁体Paramagnetic 正磁化率Positive magnetic susceptibility铁磁体Ferromagnetism 转变元素Transition element交换能量Positive energy exchange外价电子Outer valence electrons化学结合Chemical bond自发上磁Spontaneous magnetization磁畴Magnetic domain相反旋转Opposite span比较抗磁体、顺磁体及铁磁体Comparison of Diamagnetism, Paramagnetic & Ferromagnetism 反铁磁体Antiferromagnetism 亚铁磁体Ferrimagnetism 磁矩magnetic moment净磁矩Net magnetic moment钢铁的主要成份The major element of steel 钢铁用"碳"之含量来分类Classification of Steel according to Carbon contents铁相Steel Phases钢铁的名称Name of steel纯铁体Ferrite渗碳体Cementitle奥氏体Austenite珠光体及共释钢Pearlite &Eutectoid 奥氏体碳钢Austenite Carbon Steel 单相金属Single Phase Metal 共释变态Eutectoid Transformation 珠光体Pearlite亚铁释体Hyppo-Eutectoid 初释纯铁体Pro-entectoid ferrite过共释钢Hype-eutectoid 珠光体Pearlite 粗珠光体Coarse pearlite中珠光体Medium pearlite幼珠光体Fine pearlite磁性变态点Magnetic Transformation 钢铁的制造Manufacturing of Steel 连续铸造法Continuous casting process电炉Electric furnace均热炉Soaking pit 全静钢Killed steel半静钢Semi-killed steel沸腾钢(未净钢) Rimmed steel钢铁生产流程Steel Production Flow Chart 钢材的熔铸、锻造、挤压及延轧The Casting, Fogging, Extrusion, Rolling & Steel 熔铸Casting锻造Fogging挤压Extrusion延轧Rolling冲剪Drawing & stamping特殊钢Special Steel简介General特殊钢以原素分类Classification of Special Steel according to Element 特殊钢以用途来分类Classification of Special Steel according to End Usage 易车(快削)不锈钢Free Cutting Stainless Steel 含铅易车钢Leaded Free Cutting Steel 含硫易车钢Sulphuric Free Cutting Steel 硬化性能Hardenability 钢的脆性Brittleness of Steel 低温脆性Cold brittleness回火脆性Temper brittleness日工标准下的特殊钢材Specail Steel according to JIS Standard铬钢–日工标准JIS G4104Chrome steel to JIS G4104 铬钼钢钢材–日工标准G4105 62Chrome Molybdenum steel to JIS G4105 镍铬–日工标准G410263Chrome Nickel steel to JIS G4102 镍铬钼钢–日工标准G4103 64Nickel, Chrome & Molybdenum Steel to JIS G4103 高锰钢铸–日工标准High manganese steel to JIS standard材料的加工性能Drawing abillity防止生锈Rust Protection 生锈速度表Speed of rusting焊接Welding气焊Gas Welding埋弧焊Submerged-arc Welding电阻焊Resistance Welding点焊Spot welding滚焊Seam welding 锌镀层质量Zinc Coating Mass表面处理Surface Treatment 冷轧钢片Cold-Rolled Steel Sheet/Strip 热轧钢片Hot-Rolled Sheet/Strip长度公差Length Tolerance理论质量Theoretical Mass钢的种类Type of Steel表面处理Surface Finish 常用尺寸Commonly Used Size软磁材料Soft Magnetic Material 滞后回线Narrow Hystersis 矫顽磁力Coercive Force 硬磁材料Hard Magnetic Material最大能量积Maximum Energy Product 退火时注意事项Annealing Precautionary碳污染Prevent Carbon Contamination热力应先从工件边缘透入Heat from the Laminated Stacks Edges提防过份氧化No Excessive Oxidation绝缘表面Surface Insulation电器及家电外壳用镀层冷辘[低碳] 钢片Coated (Low Carbon) Steel Sheets forCasing,Electricals & Home Appliances镀铝硅钢片Aluminized Silicon Alloy Steel Sheet 镀铝硅合金钢片的特色Feature of Aluminized Silicon Alloy Steel Sheet 抗化学品能力Chemical Resistance 镀铝(硅)钢片–日工标准(JIS G3314)Hot-aluminum-coated sheets and coils to JIS G 3314 镀铝(硅)钢片–美材试标准(ASTM A-463-77)35.7 JIS G3314镀热浸铝片的机械性能Mechanical Properties of JIS G 3314 Hot-Dip Aluminum-coated Sheets and Coils镀铝(硅)钢片及其它种类钢片的抗腐蚀性能比较Comparsion of various resistance of aluminized steel & other kinds of steel镀铝(硅)钢片生产流程Aluminum Steel Sheet, Production Flow Chart 焊接能力Weldability 镀铝钢片的焊接状态(比较冷辘钢片) Tips on welding of Aluminized sheet in comparasion with cold rolled steel strip钢板Steel Plate钢板用途分类及各国钢板的工业标准包括日工标准及美材试标准Type of steel Plate & Related JIS, ASTM and Other Major Industrial Standards钢板生产流程Production Flow Chart不锈钢Stainless Steel不锈钢的定义Definition of Stainless Steel不锈钢之分类,耐腐蚀性及耐热性Classification, Corrosion Resistant & Heat Resistance of Stainless Steel 铁铬系不锈钢片ChromeStainless Steel 马氏体不锈钢Martensite Stainless Steel 低碳马氏体不锈钢Low Carbon Martensite Stainless Steel 含铁体不锈钢Ferrite Stainless Steel 镍铬系不锈钢Nickel Chrome Stainless Steel 释出硬化不锈钢Precipitation Hardening Stainless Steel 铁锰铝不锈钢Fe / Mn / Al / Stainless Steel 不锈钢的磁性Magnetic Property & Stainless Steel 不锈钢箔、卷片、片及板之厚度分类Classification of Foil, Strip, Sheet & Plate by Thickness 表面保护胶纸Surface protection film不锈钢片材常用代号Designation of SUS Steel Special Use Stainless 不锈钢片机械性能(301, 304, 631, CSP)Mechanical Properties of Spring use Stainless Steel 不锈钢–种类,工业标准,化学成份,特点及主要用途Stainless Steel – Type, Industrial Standard, Chemical Composition, Characteristic & end usage of the most commonly used Stainless Steel不锈钢片、板用途例Examples of End Usages of Strip, Sheet & Plate 不锈钢应力退火卷片常用规格名词图解General Specification of Tension Annealed Stainless Steel Strips 耐热不锈钢Heat-Resistance Stainless Steel 镍铬系耐热不锈钢特性、化学成份、及操作温度Heat-Resistance Stainless Steel 铬系耐热钢Chrome Heat Resistance Steel 镍铬耐热钢Ni - Cr Heat Resistance Steel 超耐热钢Special Heat Resistance Steel 抗热超级合金Heat Resistance Super Alloy 耐热不锈钢比重表Specific Gravity of Heat – resistance steel plates and sheets stainless steel 不锈钢材及耐热钢材标准对照表Stainless and Heat-Resisting Steels 边缘处理Edge Finish硬度Hardness高碳钢化学成份及用途High Carbon Tool Steel, Chemical Composition and Usage 高碳钢片High Carbon Steel Strip 用组织结构分类Classification According to Grain Structure 用含碳量分类–即低碳钢、中碳钢及高碳钢Classification According to Carbon Contains弹簧用碳钢片CarbonSteel Strip For Spring Use 冷轧状态Cold Rolled Strip回火状态Annealed Strip淬火及回火状态Hardened & Tempered Strip/ Precision – Quenched Steel Strip 贝氏体钢片Bainite Steel Strip弹簧用碳钢片材之边缘处理Edge Finished 淬火剂Quenching Media碳钢回火Tempering回火有低温回火及高温回火Low&High Temperature Tempering高温回火High Temperature Tempering退火Annealing完全退火Full Annealing扩散退火Diffusion Annealing低温退火Low Temperature Annealing中途退火Process Annealing球化退火Spheroidizing Annealing光辉退火Bright Annealing淬火Quenching时间淬火Time Quenching奥氏铁孻回火Austempering马氏铁体淬火Marquenching高碳钢片用途End Usage of High Carbon Steel Strip冷轧高碳钢–日本工业标准Cold-Rolled (Special Steel) Carbon Steel Strip to JIS G3311 电镀金属钢片Plate Metal Strip金属捆片电镀层Plated Layer of Plated Metal Strip 镀镍Nickel Plated 镀铬ChromePlated镀黄铜Brass Plated 基层金属Base Metal of Plated Metal Strip低碳钢或铁基层金属Iron & Low Carbon as Base Metal 不锈钢基层金属Stainless Steel as Base Metal铜基层金属Copper as Base Metal 黄铜基层金属Brass as Base Metal轴承合金Bearing Alloy 简介General轴承合金–日工标准JIS H 5401Bearing Alloy to JIS H 5401 锡基、铅基及锌基轴承合金比较表Comparison of Tin base, Lead base and Zinc base alloy for Bearing purpose易溶合金Fusible Alloy焊接合金Soldering and Brazing Alloy机械性能Mechanical Properites 冷冲及冷锻用碳钢线枝Carbon Steel Wire Rods for Cold Heading & Cold Forging (to JIS G3507)级别,代号及化学成份Classification, Symbol of Grade and Chemical Composition 冷拉钢枝材Cold Drawn Carbon Steel Shafting Bar冷拉钢板重量表Cold Drawn Steel Bar Weight Table 高碳钢High Carbon Steel冷拉高碳钢线Hard Drawn High Carbon Steel Wire(to JIS G3521, ISO-84580-1&2)化学成份分析表Chemical Analysis of Wire Rod 级别,代号,扭曲特性及可用之线材直径Classes, symbols, twisting characteristic and applied Wire Diameters 直径,公差及拉力强度Diameter, Tolerance and Tensile Strength 裂纹之容许深度及脱碳层Permissible depth of flaw and decarburized layer 常用的弹簧不锈钢线-编号,特性,表面处理及化学成份StainlessSpring Wire – National Standard number, Charateristic, Surface finish & Chemical composition处理及表面状况Finish & Surface 铬镍不锈钢及抗热钢弹簧线材–美国材验学会ASTM A313 –1987Chromium – Nickel Stainless and Heat-resisting Steel Spring Wire – ASTMA313 – 1987化学成份Chemical Composition机械性能Mechanical Properties 易车碳钢Free Cutting Carbon Steels (to JIS G4804 ) 易车(快削)不锈钢Free Cutting Stainless Steel加工方法Manufacturing Method 应用材料Material Used 特点Characteristic 用途End Usages材料的类型Types of materials, metals, ceramics, polymers, composites, elastomer电导率和电阻率conductivity and resistivity,热导率thermal conductivity, 应力和应变stress and strain,弹性应变elastic strain, 塑性应变plastic strain, 屈服强度yield strength, 最大抗拉强度ultimate tensile strength, 最大强度ultimate strength, 延展性ductility, 伸长率elongation, 断面收缩率reduction of area, 颈缩necking, 断裂强度breaking strength, 韧性toughness,硬度hardness,疲劳强度fatigue strength, 蜂窝honeycomb, 热脆性heat shortness,晶胞中的原子数atoms per cell, 点阵lattice, 阵点lattice point, 点阵参数lattice parameter,密排六方hexagonal close-packed, 六方晶胞hexagonal unit cell,体心立方body-centered cubic, 面心立方face-centered cubic, 弥勒指数Miller indices, 晶面crystal plane, 晶系crystal system, 晶向crystal direction,相变机理Phase transformation mechanism: 成核生长相变nucleation–growth transition, 斯宾那多分解spinodal decomposition, 有序无序转变disordered-order transition, 马氏体相变martensite phase transformation,成核nucleation, 成核机理nucleation mechanism, 成核势垒nucleation barrier, 晶核,结晶中心nucleus of crystal, 金属组织的)基体quay, 基体,基块,基质,结合剂matrix, 子晶,雏晶matted crystal, 耔晶,晶种seed crystal, 耔晶取向seed orientation, 籽晶生长seeded growth, 均质核化homogeneous nucleation, 异质核化heterogeneous nucleation, 均匀化热处理homogenization heat treatment, 熟料grog,自恰场self-consistent field固溶体Solid solution: 有序固溶体ordered solid solution, 无序固溶体disordered solid solution, 有序合金orderedalloy, 无序合金disordered alloy. 无序点阵disordered lattice, 分散,扩散,弥散dispersal, 分散剂dispersant, 分散剂,添加剂dispersant additive, 分散剂,弥散剂dispersant agent缺陷defect, imperfection, 点缺陷point defect,线缺陷line defect, dislocation, 面缺陷interface defect, surface defect, 体缺陷volume defect, 位错排列dislocation arrangement, 位错阵列dislocation array, 位错气团dislocation atmosphere, 位错轴dislocation axis, 位错胞dislocation cell, 位错爬移dislocation climb, 位错滑移dislocation slip, dislocation movement by slip, 位错聚结dislocation coalescence, 位错核心能量dislocation core energy, 位错裂纹dislocation crack, 位错阻尼dislocation damping, 位错密度dislocation density, 体积膨胀volume dilation, 体积收缩volume shrinkage,回火tempering, 退火annealing, 退火的,软化的softened, 软化退火,软化(处理)softening, 淬火quenching, 淬火硬化quenching hardening, 正火normalizing, normalization, 退火织构annealing texture, 人工时效artificial aging,细长比aspect ratio, 形变热处理ausforming, 等温退火austempering, 奥氏体austenite, 奥氏体化austenitizing,贝氏体bainite, 马氏体martensite, 马氏体淬火marquench, 马氏体退火martemper, 马氏体时效钢maraging steel, 渗碳体cementite, 固溶强化solid solution strengthening,钢屑混凝土steel chips concrete, 水玻璃,硅酸钠sodium silicate, 水玻璃粘结剂sodium silicate binder, 硅酸钠类防水剂sodium silicate waterproofing agent,扩散diffusion, 扩散系数diffusivity, 相变phase transition, 烧结sintering, 固相反应solid-phase reaction,相图与相结构phase diagrams and phase structures , 相phase, 组分component, 自由度freedom, 相平衡phase equilibrium, 吉布斯相律Gibbs phase rule, 吉布斯自由能Gibbs free energy, 吉布斯混合能Gibbs energy of mixing, 吉布斯熵Gibbs entropy, 吉布斯函数Gibbs function, 相平衡phase balance, 相界phase boundary, 相界线phase boundary line, 相界交联phase boundary crosslinking, 相界有限交联phase boundary crosslinking, 相界反应phase boundary reaction, 相变phase change, 相组成phase composition, 共格相phase-coherent, 金相相组织phase constentuent, 相衬phase contrast, 相衬显微镜phase contrast microscope,相衬显微术phase contrast microscopy, 相分布phase distribution, 相平衡常数phase equilibrium constant, 相平衡图phase equilibrium diagram, 相变滞后phase transition lag, Al-Si-O-N 系统相关系phase relationships in the Al-Si-O-N system, 相分离phase segregation, phase separation, 玻璃分相phase separation in glasses, 相序phase order, phase sequence, 相稳定性phase stability, 相态phase state, 相稳定区phase stabile range, 相变温度phase transition temperature, 相变压力phase transition pressure, 同质多晶转变polymorphic transformation, 相平衡条件phase equilibrium conditions, 显微结构microstructures, 不混溶固溶体immiscible solid solution, 转熔型固溶体peritectic solid solution, 低共熔体eutectoid,crystallization, 不混溶性immiscibility, 固态反应solid state reaction, 烧结sintering, 相变机理Phase transformation mechanism: 成核生长相变nucleation–growth transition, 斯宾那多分解spinodal decomposition, 有序无序转变disordered-order transition, 马氏体相变martensite phase transformation,成核nucleation, 成核机理nucleation mechanism, 成核势垒nucleationbarrier, 晶核,结晶中心nucleus of crystal, (金属组织的)基体quay, 基体,基块,基质,结合剂matrix, 子晶,雏晶matted crystal, 耔晶,晶种seed crystal, 耔晶取向seed orientation, 籽晶生长seeded growth, 均质核化homogeneous nucleation, 异质核化heterogeneous nucleation, 均匀化热处理homogenization heat treatment,。
Material Science 材料科学Material Science Definition 材料科学定义Machinability[məʃi:nə'biliti]加工性能Strength .[streŋθ]强度Corrosion & resistance durability.[kə'rəʊʒən] &[ri'zistəns] .[ 'djʊrə'bɪlətɪ] 抗腐蚀及耐用Special metallic features 金属特性Allergic, re-cycling & environmental protection 抗敏感及环境保护Chemical element 化学元素Atom of Elements 元素的原子序数Atom and solid material 原子及固体物质Atom Constitutes 原子的组织图Periodic Table 周期表Atom Bonding 原子键结合Metal and Alloy 金属与合金Ferrous & Non Ferrous Metal 铁及非铁金属Features of Metal 金属的特性Crystal Pattern 晶体结构Crystal structure, Space lattice & Unit cell 晶体结构,定向格子及单位晶格X – ray crystal analytics method X线结晶分析法Metal space lattice 金属结晶格子Lattice constant 点阵常数Mill's Index 米勒指数Metal Phase and Phase Rule金相及相律Solid solution 固熔体Substitutional type solid solution 置换固熔体Interstitial solid solution 间隙固熔体Intermetallic compound 金属间化合物Transformation 转变Transformation Point 转变点Magnetic Transformation 磁性转变Allotropic Transformation 同素转变Thermal Equilibrium 热平衡Degree of freedom 自由度Critical temperature 临界温度Eutectic 共晶Peritectic [.peri’tekti k] Temperature包晶温度Peritectic Reaction 包晶反应Peritectic Alloy 包晶合金Hypoeutectic Alloy 亚共晶体Hypereutectic Alloy 过共晶体Plastic Deformation 金属塑性Slip Plan 滑动面Distortion 畸变Work Hardening 硬化Annealing 退火Crystal Recovery 回复柔软Recrystallization 再结晶Properties & testing of metal 金属材料的性能及试验Chemical Properties 化学性能Physical Properties 物理性能Magnetism 磁性Specific resistivity & specific resistance 比电阻Specific gravity & specific density比重Specific Heat比热热膨胀系数 Coefficient of thermal expansion导热度 Heat conductivity机械性能 Mechanical properties屈服强度(降伏强度) (Yield strength)弹性限度、杨氏弹性系数及屈服点 elastic limit, Young’s module of elasticity to yield point伸长度 Elongation断面缩率 Reduction of area破坏性检验 destructive inspections渗透探伤法 Penetrate inspection磁粉探伤法 Magnetic particle inspection放射线探伤法 Radiographic inspection超声波探伤法 Ultrasonic inspection显微观察法 Microscopic inspection破坏的检验 Destructive Inspection冲击测试 Impact Test疲劳测试 Fatigue Test蠕变试验Creep Test潜变强度 Creeps Strength第一潜变期 Primary Creep第二潜变期 Secondary Creep第三潜变期 Tertiary Creep主要金属元素之物理性质 Physical properties of major Metal Elements工业标准及规格–铁及非铁金属 Industrial Standard – Ferrous & Non – ferrous Metal磁力 Magnetic简介 General软磁 Soft Magnetic硬磁 Hard Magnetic磁场 Magnetic Field磁性感应 Magnetic Induction导磁率[系数,性] Magnetic Permeability磁化率 Magnetic Susceptibility (Xm)磁力(Magnetic Force)及磁场 (Magnetic Field)是因物料里的电子 (Electron)活动而产生抗磁体、顺磁体、铁磁体、反铁磁体及亚铁磁体 Diamagnetism, Paramagnetic, Ferromagnetisms, Antiferromagnetism & Ferrimagnetisms抗磁体 Diamagnetism磁偶极子 Dipole负磁力效应 Negative effect顺磁体 Paramagnetic正磁化率 Positive magnetic susceptibility铁磁体 Ferromagnetism转变元素 Transition element交换能量 Positive energy exchange外价电子 Outer valence electrons化学结合 Chemical bond自发上磁 Spontaneous magnetization磁畴 Magnetic domain相反旋转 Opposite span比较抗磁体、顺磁体及铁磁体 Comparison of Diamagnetism, Paramagnetic & Ferromagnetism反铁磁体 Antiferromagnetism亚铁磁体 Ferrimagnetism磁矩 magnetic moment净磁矩 Net magnetic moment钢铁的主要成份 The major element of steel钢铁用"碳"之含量来分类 Classification of Steel according to Carbon contents铁相 Steel Phases钢铁的名称 Name of steel铁素体Ferrite渗碳体 Cementitle奥氏体 Austenite珠光体及共析钢 Pearlite &Eutectoid奥氏体碳钢 Austenite Carbon Steel单相金属 Single Phase Metal共释变态 Eutectoid Transformation珠光体 Pearlite亚铁释体 Hyppo-Eutectoid初释纯铁体 Pro-entectoid ferrite过共释钢 Hype-eutectoid粗珠光体 Coarse pearlite中珠光体 Medium Pearlite幼珠光体 Fine pearlite磁性变态点 Magnetic Transformation钢铁的制造 Manufacturing of Steel连续铸造法 Continuous casting process电炉 Electric furnace均热炉 Soaking pit全静钢 Killed steel半静钢 Semi-killed steel沸腾钢(未净钢) Rimmed steel钢铁生产流程 Steel Production Flow Chart钢材的熔铸、锻造、挤压及延轧 The Casting, Fogging, Extrusion, Rolling & Steel熔铸 Casting锻造 Fogging挤压 Extrusion延轧Rolling冲剪 Drawing & stamping特殊钢以元素分类Classification of Special Steel according to Element特殊钢以用途来分类 Classification of Special Steel according to End Usage 易车(快削)不锈钢 Free Cutting Stainless Steel含铅易车钢 Leaded Free Cutting Steel含硫易车钢 Sulphuric Free Cutting Steel硬化性能 Hardenability钢的脆性 Brittleness of Steel低温脆性 Cold brittleness回火脆性 Temper brittleness日工标准下的特殊钢材 Specail Steel according to JIS Standard铬钢–日工标准 JIS G4104 Chrome steel to JIS G4104铬钼钢钢材–日工标准 G4105 62 Chrome Molybdenum steel to JIS G4105镍铬–日工标准 G4102 63 Chrome Nickel steel to JIS G4102镍铬钼钢–日工标准 G4103 64 Nickel, Chrome & Molybdenum Steel to JIS G4103高锰钢铸–日工标准 High manganese steel to JIS standard片及板材 Chapter Four-Strip, Steel & Plate冷辘低碳钢片(双单光片)(日工标准 JIS G3141) 73 - 95 Cold Rolled (Low carbon) Steel Strip (to JIS G 3141)简介 General美材试标准的冷辘低碳钢片 Cold Rolled Steel Strip American Standard – American Society for testing and materials (ASTM)日工标准 JIS G3141冷辘低碳钢片 (双单光片)的编号浅释 Decoding of cold rolled(Low carbon)steel strip JIS G3141材料的加工性能 Drawing ability硬度 Hardness表面处理 Surface finish冷辘钢捆片及张片制作流程图表 Production flow chart cold rolled steel coil sheet冷辘钢捆片及张片的电镀和印刷方法 Cold rolled steel coil & sheet electro-plating & painting method冷辘(低碳)钢片的分类用途、工业标准、品质、加热状态及硬度表 End usages, industrial standard, quality, condition and hardness of cold rolled steel strip硬度及拉力 Hardness & Tensile strength test拉伸测试(顺纹测试) Elongation test杯突测试(厚度: 0.4公厘至 1.6公厘,准确至 0.1公厘 3个试片平均数 ) Erichsen test (Thickness: 0.4mm to 1.6mm, figure round up to 0.1mm)曲面(假曲率) Camber厚度及阔度公差 Tolerance on Thickness & Width平坦度(阔度大于 500公厘,标准回火 ) Flatness (width>500mm, temper: standard)弯度 Camber冷辘钢片储存与处理提示 General advice on handling & storage of cold rolled steel coil & sheet 防止生锈 Rust Protection生锈速度表 Speed of rusting焊接 Welding气焊 Gas Welding埋弧焊 Submerged-arc Welding电阻焊 Resistance Welding冷辘钢片(拉力: 30-32公斤/平方米)在没有表面处理状态下的焊接状况 Spot welding conditions for bared (free from paint, oxides etc) Cold rolled mild steel sheets(T/S:30-32 Kgf/ µ m2)时间效应(老化)及拉伸应变 Aging & Stretcher Strains日工标准(JIS G3141)冷辘钢片化学成份 Chemical composition – cold rolled steel sheet to JIS G3141冷辘钢片的"理论重量"计算方程式 Cold Rolled Steel Sheet – Theoretical mass 日工标准(JIS G3141)冷辘钢片重量列表 Mass of Cold-Rolled Steel Sheet to JIS G3141冷辘钢片订货需知Ordering of cold rolled steel strip/sheet其它日工标准冷轧钢片(用途及编号) JIS standard & application of other cold Rolled Special Steel电镀锌钢片或电解钢片Electro-galvanized Steel Sheet/Electrolytic Zinc Coated Steel Sheet电解/电镀锌大大增强钢片的防锈能力Galvanic Action improving Weather & Corrosion Resistance of the Base Steel Sheet上漆能力 Paint Adhesion电镀锌钢片的焊接 Welding of Electro-galvanized steel sheet点焊 Spot welding滚焊 Seam welding电镀锌(电解)钢片 Electro-galvanized Steel Sheet生产流程 Production Flow Chart常用的镀锌钢片(电解片)的基层金属、用途、日工标准、美材标准及一般厚度 Base metal, application, JIS & ASTM standard, and Normal thickness of galvanized steel sheet锌镀层质量 Zinc Coating Mass表面处理 Surface Treatment冷轧钢片 Cold-Rolled Steel Sheet/Strip热轧钢片 Hot-Rolled Sheet/Strip电解冷轧钢片厚度公差 Thickness Tolerance of Electrolytic Cold-rolled sheet热轧钢片厚度公差 Thickness Tolerance of Hot-rolled sheet冷轧或热轧钢片阔度公差 Width Tolerance of Cold or Hot-rolled sheet长度公差 Length Tolerance理论质量 Theoretical Mass锌镀层质量(两个相同锌镀层厚度) Mass Calculation of coating (For equal coating)/MM锌镀层质量(两个不同锌镀层厚度) Mass Calculation of coating (For differential coating)/MM镀锡薄铁片(白铁皮/马口铁) (日工标准 JIS G3303)简介 General镀锡薄铁片的构造 Construction of Electrolytic Tinplate镀锡薄钢片(白铁皮/马日铁)制造过程 Production Process of Electrolytic Tinplate锡层质量 Mass of Tin Coating (JIS G3303-1987)两面均等锡层 Both Side Equally Coated Mass两面不均等锡层 Both Side Different Thickness Coated Mass级别、电镀方法、镀层质量及常用称号Grade, Plating type, Designation of Coating Mass & Common Coating Mass镀层质量标记 Markings & Designations of Differential Coatings硬度 Hardness单相轧压镀锡薄铁片(白铁皮/马口铁) Single-Reduced Tinplate双相辗压镀锡薄钢片(马口铁/白铁皮) Dual-Reduction Tinplate钢的种类 Type of Steel常用尺寸 Commonly Used Size电器用硅 [硅] 钢片 Electrical Steel Sheet简介 General软磁材料 Soft Magnetic Material滞后回线 Narrow Hysteresis矫顽磁力 Coercive Force硬磁材料 Hard Magnetic Material最大能量积 Maximum Energy Product硅含量对电器用的低碳钢片的最大好处 The Advantage of Using Silicon low Carbon Steel晶粒取向(Grain-Oriented)及非晶粒取向(Non-Oriented) Grain Oriented & Non-Oriented电器用硅 [硅] 钢片的最终用途及规格 End Usage and Designations of Electrical Steel Strip电器用的硅 [硅] 钢片之分类 Classification of Silicon Steel Sheet for Electrical Use电器用钢片的绝缘涂层 Performance of Surface Insulation of Electrical Steel Sheets晶粒取向电器用硅钢片主要工业标准 International Standard – Grain-Oriented Electrical Steel Silicon Steel Sheet for Electrical Use晶粒取向电器用硅钢片 Grain-Oriented Electrical Steel晶粒取向,定取向芯钢片及高硼定取向芯钢片之磁力性能及夹层系数 (日工标准及美材标准) Magnetic Properties and Lamination Factor of SI-ORIENT-CORE& SI-ORIENT-CORE-HI B Electrical Steel Strip (JIS and AISI Standard)退火 Annealing电器用钢片用家需自行应力退火原因 Annealing of the Electrical Steel Sheet退火时注意事项 Annealing Precautionary碳污染 Prevent Carbon Contamination热力应先从工件边缘透入 Heat from the Laminated Stacks Edges提防过份氧化 No Excessive Oxidation应力退火温度 Stress –relieving Annealing Temperature绝缘表面 Surface Insulation非晶粒取向电力用钢片的电力、磁力、机械性能及夹层系数 Lamination Factors of Electrical, Magnetic & Mechanical Non-Grain Oriented Electrical电器及家电外壳用镀层冷辘 [低碳] 钢片 Coated (Low Carbon) Steel Sheets for Casing,Electricals & Home Appliances镀铝硅钢片 Aluminized Silicon Alloy Steel Sheet镀铝硅合金钢片的特色 Feature of Aluminized Silicon Alloy Steel Sheet用途 End Usages抗化学品能力 Chemical Resistance镀铝(硅)钢片–日工标准 (JIS G3314) Hot-aluminum-coated sheets and coils to JIS G 3314镀铝(硅)钢片–美材试标准 (ASTM A-463-77)35.7 JIS G3314镀热浸铝片的机械性能 Mechanical Properties of JIS G 3314 Hot-Dip Aluminum-coated Sheets andCoils公差 Size Tolerance镀铝(硅)钢片及其它种类钢片的抗腐蚀性能比较 Comparsion of various resistance of aluminized steel & other kinds of steel镀铝(硅)钢片生产流程 Aluminum Steel Sheet, Production Flow Chart焊接能力 Weldability镀铝钢片的焊接状态(比较冷辘钢片) Tips on welding of Aluminized sheet in comparasion with cold rolled steel strip钢板 Steel Plate钢板用途分类及各国钢板的工业标准包括日工标准及美材试标准 Type of steel Plate & Related JIS, ASTM and Other Major Industrial Standards钢板生产流程 Production Flow Chart钢板订货需知 Ordering of Steel Plate不锈钢 Stainless Steel不锈钢的定义 Definition of Stainless Steel不锈钢之分类,耐腐蚀性及耐热性 Classification, Corrosion Resistant & Heat Resistance of Stainless Steel铁铬系不锈钢片Chrome Stainless Steel马氏体不锈钢Martensite Stainless Steel低碳马氏体不锈钢Low Carbon Martensite Stainless Steel含铁体不锈钢Ferrite Stainless Steel镍铬系不锈钢Nickel Chrome Stainless Steel释出硬化不锈钢Precipitation Hardening Stainless Steel铁锰铝不锈钢Fe / Mn / Al / Stainless Steel不锈钢的磁性Magnetic Property & Stainless Steel不锈钢箔、卷片、片及板之厚度分类Classification of Foil, Strip, Sheet & Plate by Thickness表面保护胶纸Surface protection film不锈钢片材常用代号Designation of SUS Steel Special Use Stainless 表面处理 Surface finish 薄卷片及薄片(0.3至 2.9mm 厚之片)机械性能Mechanical Properties of Thin Stainless Steel(Thickness from 0.3mm to 2.9mm) – strip/sheet 不锈钢片机械性能(301, 304, 631, CSP) Mechanical Properties of Spring use Stainless Steel不锈钢–种类,工业标准,化学成份,特点及主要用途Stainless Steel – Type, Industrial Standard, Chemical Composition, Characteristic & end usage of the most commonly used Stainless Steel不锈钢薄片用途例End Usage of Thinner Gauge不锈钢片、板用途例Examples of End Usages of Strip, Sheet & Plate不锈钢应力退火卷片常用规格名词图解General Specification of Tension Annealed Stainless Steel Strips耐热不锈钢Heat-Resistance Stainless Steel镍铬系耐热不锈钢特性、化学成份、及操作温度Heat-Resistance Stainless Steel铬系耐热钢Chrome Heat Resistance Steel镍铬耐热钢Ni - Cr Heat Resistance Steel超耐热钢Special Heat Resistance Steel抗热超级合金Heat Resistance Super Alloy耐热不锈钢比重表Specific Gravity of Heat – resistance steel plates and sheets stainless steel不锈钢材及耐热钢材标准对照表Stainless and Heat-Resisting Steels发条片 Power Spring Strip发条的分类及材料 Power Spring Strip Classification and Materials上链发条 Wind-up Spring倒后擦发条 Pull Back Power Spring圆面("卜竹")发条 Convex Spring Strip拉尺发条 Measure Tape魔术手环 Magic Tape魔术手环尺寸图 Drawing of Magic Tap定型发条 Constant Torque Spring定型发条及上炼发条的驱动力 Spring Force of Constant Torque Spring and Wing-up Spring定型发条的形状及翻动过程 Shape and Spring Back of Constant Torque Spring定型发条驱动力公式及代号The Formula and Symbol of Constant Torque Spring边缘处理 Edge Finish硬度 Hardness高碳钢化学成份及用途 High Carbon Tool Steel, Chemical Composition and Usage每公斤发条的长度简易公式 The Length of 1 Kg of Spring Steel Strip SK-5 & AISI-301每公斤长的重量 /公斤(阔 100-200公厘) Weight per one meter long (kg) (Width 100-200mm) SK-5 & AISI-301每公斤之长度 (阔 100-200公厘) Length per one kg (Width 100-200mm) SK-5 & AISI-301每公尺长的重量 /公斤(阔 2.0-10公厘) Weight per one meter long (kg) (Width 2.0-10mm) SK-5 & AISI-301每公斤之长度 (阔 2.0-10公厘) Length per one kg (Width 2.0-10mm)高碳钢片 High Carbon Steel Strip分类 Classification用组织结构分类 Classification According to Grain Structure用含碳量分类–即低碳钢、中碳钢及高碳钢 Classification According to Carbon Contains弹簧用碳钢片 Carbon Steel Strip For Spring Use冷轧状态 Cold Rolled Strip回火状态 Annealed Strip淬火及回火状态 Hardened & Tempered Strip/ Precision – Quenched Steel Strip贝氏体钢片 Bainite Steel Strip弹簧用碳钢片材之边缘处理 Edge Finished淬火剂 Quenching Media碳钢回火 Tempering回火有低温回火及高温回火 Low & High Temperature Tempering高温回火 High Temperature Tempering退火 Annealing完全退火 Full Annealing扩散退火 Diffusion Annealing低温退火 Low Temperature Annealing中途退火 Process Annealing球化退火 Spheroidizing Annealing光辉退火 Bright Annealing淬火 Quenching时间淬火 Time Quenching奥氏铁孻回火 Austempering马氏铁体淬火 Marquenching高碳钢片用途 End Usage of High Carbon Steel Strip冷轧高碳钢–日本工业标准 Cold-Rolled (Special Steel) Carbon Steel Strip to JIS G3311电镀金属钢片 Plate Metal Strip电镀金属捆片的优点Advantage of Using Plate Metal Strip金属捆片电镀层 Plated Layer of Plated Metal Strip镀镍 Nickel Plated镀铬 Chrome Plated镀黄铜 Brass Plated基层金属 Base Metal of Plated Metal Strip低碳钢或铁基层金属 Iron & Low Carbon as Base Metal不锈钢基层金属 Stainless Steel as Base Metal铜基层金属 Copper as Base Metal黄铜基层金属 Brass as Base Metal轴承合金 Bearing Alloy轴承合金–日工标准 JIS H 5401 Bearing Alloy to JIS H 5401锡基、铅基及锌基轴承合金比较表 Comparison of Tin base, Lead base and Zinc base alloy for Bearing purpose易溶合金 Fusible Alloy焊接合金 Soldering and Brazing Alloy软焊 Soldering Alloy软焊合金–日本标准 JIS H 4341 Soldering Alloy to JIS H 4341硬焊 Brazing Alloy其它焊接材料请参阅日工标准目录 Other Soldering Material细线材、枝材、棒材 Chapter Five Wire, Rod & Bar线材/枝材材质分类及制成品 Classification and End Products of Wire/Rod铁线(低碳钢线)日工标准 JIS G 3532 Low Carbon Steel Wires ( Iron Wire ) to JIS G 3532光线(低碳钢线),火线 (退火低碳钢线 ),铅水线 (镀锌低碳钢线)及制造钉用低碳钢线之代号、公差及备注 Ordinary Low Carbon Steel Wire, Annealed Low Carbon Steel Wire, Galvanized low Carbon Steel Wire & Low Carbon Steel Wire for nail manufacturing - classification, Symbol of Grade, Tolerance and Remarks.机械性能 Mechanical Properites锌包层之重量,铜硫酸盐试验之酸洗次数及测试用卷筒直径 Weight of Zinc-Coating, Number of Dippings in Cupric Sulphate Test and Diameters of Mandrel Used for Coiling Test冷冲及冷锻用碳钢线枝 Carbon Steel Wire Rods for Cold Heading & Cold Forging (to JIS G3507) 级别,代号及化学成份 Classification, Symbol of Grade and Chemical Composition直径公差,偏圆度及脱碳层的平均深度 Diameter Tolerance, Ovality and Average Decarburized Layer Depth冷拉钢枝材 Cold Drawn Carbon Steel Shafting Bar枝材之美工标准,日工标准,用途及化学成份 AISI, JIS End Usage and Chemical Composition of Cold Drawn Carbon Steel Shafting Bar冷拉钢板重量表 Cold Drawn Steel Bar Weight Table高碳钢线枝 High Carbon Steel Wire Rod (to JIS G3506)冷拉高碳钢线 Hard Drawn High Carbon Steel Wire (to JIS G3521, ISO-84580-1&2)化学成份分析表 Chemical Analysis of Wire Rod线径、公差及机械性能(日本工业标准 G 3521) Mechanical Properties (JIS G 3521)琴线(日本标准 G3522) Piano Wires (to G3522)级别,代号,扭曲特性及可用之线材直径 Classes, symbols, twisting characteristic and applied WireDiameters直径,公差及拉力强度 Diameter, Tolerance and Tensile Strength裂纹之容许深度及脱碳层 Permissible depth of flaw and decarburized layer常用的弹簧不锈钢线-编号,特性,表面处理及化学成份 Stainless Spring Wire – National Standard number, Characteristic, Surface finish & Chemical composition弹簧不锈钢线,线径及拉力列表Stainless Spring Steel, Wire diameter and Tensile strength of Spring Wire处理及表面状况 Finish & Surface各种不锈钢线在不同处理拉力比较表 Tensile Strength of various kinds of Stainless Steel Wire under Different Finish圆径及偏圆度之公差 Tolerance of Wire Diameters & Ovality铬镍不锈钢及抗热钢弹簧线材–美国材验学会 ASTM A313 – 1987 Chromium – Nickel Stainless and Heat-resisting Steel Spring Wire – ASTM A313 – 1987化学成份 Chemical Composition机械性能 Mechanical Properties305, 316, 321及 347之拉力表 Tensile Strength Requirements for Types 305, 316, 321 and 347 A1S1-302贰级线材之拉力表 Tensile Strength of A1S1-302 Wire日本工业标准–不锈钢的化学成份 (先数字后字母排列) JIS –Chemical Composition of Stainless Steel (in order of number & alphabet)美国工业标准–不锈钢及防热钢材的化学成份 (先数字后字母排列) AISI – Chemical Composition of Stainless Steel & Heat-Resistant Steel(in order of number & alphabet)易车碳钢 Free Cutting Carbon Steels (to JIS G4804 )化学成份 Chemical composition圆钢枝,方钢枝及六角钢枝之形状及尺寸之公差 Tolerance on Shape and Dimensions for Round Steel Bar, Square Steel Bar, Hexagonal Steel Bar易车(快削)不锈钢 Free Cutting Stainless Steel易车(快削)不锈钢种类 Type of steel易车(快削)不锈钢拉力表 Tensile Strength of Free Cutting Wires枝/棒无芯磨公差表 (μ) (μ = 1/100 mm) Rod/Bar Centreless Grind Tolerance易车不锈钢及易车钢之不同尺寸及硬度比较 Hardness of Different Types & Size of Free Cutting Steel 扁线、半圆线及异形线 Flat Wire, Half Round Wire, Shaped Wire and Precision Shaped Fine Wire 加工方法 Manufacturing Method应用材料 Material Used特点 Characteristic用途End Usages不锈钢扁线及半圆线常用材料 Commonly used materials for Stainless Flat Wire & Half Round Wire 扁线公差 Flat Wire Tolerance方线公差 Square Wire Tolerance。
马氏体转变(十五)朱祖昌【期刊名称】《热处理技术与装备》【年(卷),期】2014(035)001【总页数】5页(P62-66)【作者】朱祖昌【作者单位】上海工程技术大学,上海201620【正文语种】中文【中图分类】TG111.55.6.2.2 TiNi合金的马氏体转变路径不够致密排列的bcc结构的母相B2具有本征的点阵不稳定(Zener不稳定)[65]。
Zener 1947年指出,在不够致密BCC的B2结构中,原子堆垛处于亚稳定状态,对抵制<110>{111}的切变将显示低的阻力,可以看成会周期性发生正反方向的<110>{111}切变,导致更致密堆垛的结构。
这种周期性的堆垛关系着特定的声子模的软化。
一般,现有大多数形状记忆合金马氏体结构是由基面、母相的{110},以不同堆垛而导得,如 B19(2H),3R,7R,9R,18R等(这在前面已有叙述,见图14)。
图38 TiNi基合金的三种马氏体转变途径Fig.38 Three martansitic transformation paths in Ti-Ni-based alloys图38指出了Ti-Ni基合金的三种马氏体转变路径。
1999年Barsch以图39来表示,图中加入了马氏体相的空间群以及除体积应变e1参数外的一级和二级对称性参数[66]。
兹分析如下:图39 TiNi合金的三种转变途径和一级二级参数(□和)结合Fig.39 Three transformation paths of TiNi alloy associated withprimary(□)and secondary( )parameter(1)B2→B19':Ti-50 at%Ni合金1273 K自母相B2淬火得到B19'马氏体,B19'具有单斜点阵,转变具有表面浮凸和热弹性特性。
(2)B2→R→B19',R相转变属马氏体转变,热滞约1~2 K。
As a high school student with a deep appreciation for the natural beauty and cultural richness of my homeland, I feel compelled to share my experiences exploring the enchanting landscapes of Jilin Province. Nestled in the northeastern part of China, Jilin boasts a plethora of scenic spots that have left indelible impressions on my heart.My journey began with the aweinspiring Changbai Mountains, a natural wonder that stands as a testament to the provinces geological majesty. The Changbai Mountains are not merely a mountain range they are a living, breathing entity that has shaped the cultural and ecological identity of the region. I remember standing at the base of the Tianchi, or Heavenly Lake, marveling at the pristine waters that lay cradled within the volcanic crater. The lakes crystalclear reflection of the surrounding peaks was a sight that transcended mere beautyit was a moment of profound connection with natures grandeur.Moving on from the mountains, I ventured to Jilin City, renowned for its winter spectaclethe Jilin Ice and Snow World. The citys transformation into a glittering ice kingdom during the cold months is nothing short of magical. I recall the exhilaration of walking through the intricately carved ice sculptures, each more fantastical than the last. The artistry and craftsmanship that go into creating these frozen masterpieces are a testament to the skill and dedication of the local artisans.Another highlight of my travels was the visit to the Wudalianchi Geopark. This geological treasure trove is a window into the earths history, with its unique volcanic landforms and mineralrich hot springs. I was particularlyfascinated by the volcanic cones and lava flows that have stood the test of time, offering a glimpse into the earths fiery past. The therapeutic properties of the hot springs were an added bonus, providing a soothing respite after a day of exploration.No trip to Jilin would be complete without a stop at the Beihu Park in Changchun. This urban oasis is a haven for nature lovers, with its lush greenery and tranquil lakes. I spent an afternoon there, watching the swans glide gracefully across the waters surface, their elegance a stark contrast to the bustling city life that surrounds the park.Cultural experiences were also a significant part of my journey. The Yanbian Korean Autonomous Prefecture offered a rich tapestry of Korean culture, from the traditional dance performances to the mouthwatering cuisine. I was particularly taken with the Jilin Provincial Museum, where I delved into the regions history and learned about its role in the ancient Silk Road trade.One of the most poignant moments of my trip was visiting the AntiJapanese War Memorial Hall in Jilin City. The exhibits there provided a stark reminder of the provinces role in the resistance against Japanese aggression during World War II. The stories of bravery and sacrifice were a humbling reminder of the resilience of the human spirit.In conclusion, Jilin Province is a treasure trove of natural beauty, cultural heritage, and historical significance. Each visit to a new site was a journey of discovery, a chance to connect with the land and its people. Thememories Ive gathered from my travels through Jilins scenic spots will forever be etched in my heart, a testament to the provinces enduring charm and allure.。
Crystal transformation from the a -to the b -form upon tensiledrawing of poly(L -lactic acid)Kazuyo Takahashi a ,Daisuke Sawai a ,Takafumi Yokoyama a ,Tetsuo Kanamoto a,*,Suong-Hyu Hyon baDepartment of Applied Chemistry,Tokyo University of Science,Kagurazaka,Shinjuku-ku,Tokyo 162-8601,Japan bInstitute for Frontier Medical Sciences,Kyoto University,53Kawara-cho,Shogoin,Sakyo-ku,Kyoto 606-8507,JapanReceived 22December 2003;received in revised form 12March 2004;accepted 24March 2004AbstractA film of poly(L -lactic acid)(PLLA)consisting of highly oriented a crystals was uniaxially drawn by tensile force.The effects of the draw ratio (DR),draw temperature ðT d Þ;and draw stress on the crystal/crystal transformation from the a -to the b -form crystals were studied.At the initial stage of drawing,the highly oriented a crystals of the starting film transformed into a broader orientation distribution,and significant crystal disorder was introduced.Upon further drawing,the a crystals steadily transformed into b crystals with increasing the DR.For the drawing at a constant T d ;the crystal transformation proceeded more efficiently at a higher draw rate and,hence,at a higher draw stress.Furthermore,for the drawing at a constant draw rate,the transformation proceeded with DR most efficiently for the tensile draw at a T d around 1408C,although the draw stress increased with decreasing the T d :The present result combined with the previous finding in the drawing of PLLA by solid-state extrusion [Macromolecules 36(2003)3601]suggests that there is a T d of around 1408C at which the crystal transformation proceeds most efficiently with DR,suggesting that there are two factors that have opposite effects on the efficiency of the crystal transformation with increasing the T d :However,as a result of the combined effects of the T d and DR on the crystal transformation and the ductility increase with the T d ;an oriented film consisting predominantly of b crystals was obtained by tensile drawing at a T d in the range of 140–1708C to the highest DR achieved at each T d :q 2004Elsevier Ltd.All rights reserved.Keywords:Tensile drawing of poly(L -lactic acid);Crystal transformation from a to b crystals;Efficiency of crystal transformation1.IntroductionMuch attention has recently been given to poly(L -lactic acid)(PLLA)because it is a polymer produced from sustainable plant products,such as corn and potato,and is biocompatible and biodegradable,producing nontoxic lactic acid in the human body [1,2].Therefore,PLLA is being used for biomedical applications,including bone-fixation devices and sutures for microsurgery [3–5].Since this polymer has good mechanical properties [6]with a high melting temperature (,1808C),its application for more general purposes,for example,as fibers [7–11],films and structural materials [12,13],has been evaluated.PLLA takes three crystal forms depending on the conditions for crystallization and drawing.The mostcommon a -form (orthorhombic)has a 10/7helical chain conformation and is obtained by crystallization from melt [7,14–16],solutions [7,16,17],or glass [18].The b -form (orthorhombic or trigonal)takes a 3/2helical conformation and is produced by drawing of a semicrystalline film with a crystals [15,19,20].Eling et al.[7]reported that b crystals were generated upon tensile drawing at a high temperature to a higher draw ratio (DR),whereas the drawing at a low temperature and/or a low DR produced a crystals.Thus,the drawn products of PLLA commonly consist of a crystals or a mixture of a and b crystals.Recently,a new g -form was obtained by epitaxial crystallization of PLLA on hexa-methylbenzene [21].This polymorph also has an ortho-rhombic unit cell containing two regularly packed antiparallel 3/2helices.Since the physical and mechanical properties as well as the chemical stability of a polymer,in general,strongly depend on the morphology and the crystal0032-3861/$-see front matter q 2004Elsevier Ltd.All rights reserved.doi:10.1016/j.polymer.2004.03.108Polymer 45(2004)4969–4976/locate/polymer*Corresponding author.structure,the conditions for the formation of the b-form crystal in PLLA should be clarified to control the properties of this polymer.Previously,we have shown that,in the solid-state extrusion of semicrystalline polymers,the deformation in an extrusion die proceeded in complex shear and exten-sionalfields under high pressure[19,22].The crystal transformation in PLLA from a crystals into oriented b crystals was promoted slightly more by shear deformation at the sheath of an extrudate than by extensional deformation at the core of the extrudate[19].Furthermore,it was found that the crystal transformation with extrusion DR proceeded most efficiently for the extrusion at1308C among the extrusion conducted at100,130,and1708C[20].In contrast to the complex deformation mode in solid-state extrusion,a simple extensional deformation may be expected for tensile drawing.In this article,we discuss the effects of the draw temperatureðT dÞ;DR,and draw stress on the a to b crystal transformation upon tensile drawing of a PLLAfilm consisting of highly oriented a crystals.Tensile drawing was made over wide ranges of temperatures and draw rates. The drawn products were characterized by wide-angle X-ray diffraction(WAXD)and polarized FT-IR spectra as a function of the DR and T d:2.Experimental section2.1.DrawingDried PLLA with a viscosity-average molecular weight ðM vÞof8.3£104was compression-molded at2008C into a film of0.1mm thickness followed by rapid cooling to ,08C.The melt-quenched amorphousfilm thus obtained had an M v of6.6£104.A ribbon with0.5cm width and 5cm length cut from the amorphousfilm was drawn by tensile force at808C to a DR of6.The drawnfilm was annealed while keeping the sample length constant at 1708C for1h,producing afilm consisting of highly oriented a crystals with high crystallinity.This highly oriented afilm was further drawn by tensile force at a T d between25and1808C and a constant crosshead speed corresponding to an initial strain rate of0.5–100/min.2.2.CharacterizationWAXD patterns were recorded by aflat-plate camera and by diffractometer scans.WAXD photographs were obtained with Cu K a radiation generated at40kV and25mA on a Rigaku Geigerflex RAD-3A and monochromatized with a graphite crystal.WAXD profiles were recorded with Ni-filtered Cu K a radiation generated at40kV and150mA on a Rigaku Rotaflex RU-200rotating anode X-ray generator equipped with a diffractometer and a pulse height discriminator.Theð00‘Þprofiles on the meridian were measured by a symmetrical transmission mode.The crystal transformation from a to b crystals was also followed by infrared(IR)spectroscopy.Polarized spectra were recorded using a JEOL Fourier transform infrared spectrometer(JRS-FT7000W)at a resolution of1cm21and room temperature.An orientedfilm consisting of a crystals (10/7helix)exhibits an absorption band at923cm21that is assigned to the CH3rocking mode,showing the transition moment perpendicular to the chain axis[23–25].In contrast,a highly oriented bfilm showed a band at 912cm21that was assigned to the CH3rocking mode of b crystals(3/2helix),which shows a transition moment perpendicular to the chain axis[20,25].The total absorbance A0for an oriented sample is given by the average of the three absorbances of A x;A y;and A z which were measured with the incident beams polarized along the three orthogonal axes of x;y;and z;respectively. For a sample uniaxially oriented along thefiber axis z;the absorbances of A x and A y may be equal[26].Thus,A0¼ðA zþ2A xÞ=3ð1ÞDensities were measured by a pycnometer method at 30.0^0.18C using pure water as afillingfluid to avoid any significant absorption of a liquid.The crystallinity of a sample was calculated assuming a crystal–amorphous two-phase structure.The densities of an amorphous phase,r a; an a crystal,r cðaÞ;and a b crystal,r cðbÞwere assumed to be 1.245^0.001g/cm3[19], 1.285g/cm3[15],and 1.301g/cm3[19],respectively.3.Results and discussion3.1.Drawing behaviorFig.1shows the WAXD patterns of an afilm prepared by drawing of an amorphousfilm at808C to a DR of6and a highly oriented sample prepared by annealing oftheFig.1.WAXD photographs of a PLLAfilm consisting of a crystals prepared by tensile drawing of an amorphousfilm at808C to a DR of6(a) and a highly orientedfilm consisting of a crystals obtained by annealing of the cold-drawnfilm at1708C for1h while keeping the sample length constant.K.Takahashi et al./Polymer45(2004)4969–4976 4970as-drawn film at 1708C for 1h while keeping the sample length constant.The WAXD of the as-drawn film shows a poor crystallinity and not well-aligned chain orientation,as revealed by the appearance of only several broad reflections overlapped with diffuse scattering.These reflections could be indexed by assuming either an orthorhombic a -form crystal [15],with unit cell constants of a ¼1:06;b ¼0:61;and c ¼2:88nm (fiber axis),or an orthorhombic b -form crystal [15,19],with cell constants of a ¼1:04;b ¼1:77;and c ¼0:90nm (fiber axis).However,the meridional scan of this sample clearly showed the existence of the (0010)a reflection from a crystals at 2u ¼31:08but no reflection at 2u ¼29:98;where the (003)b reflection from b crystals might have been observed if b crystals existed.These observations indicate that the as-drawn sample consisted of poorly oriented a crystals with significant disorder.Upon annealing of this film at 1708C,the resultant film exhibited an increased number of sharp and circular reflections from a crystals with no streak along the layer lines,showing high chain orientation and high crystal perfection as seen in Fig.1(b).Fig.2shows the nominal stress/strain curves for the tensile drawing of a highly oriented a film recorded at a constant draw temperature ðT d Þof 1708C near the melting temperature ðT m ø1808C Þand at different crosshead speeds corresponding to the initial strain rates of 0.5–100/min.When the draw was made at a lower rate,thin areas formed at several portions,and the deformation proceeded heterogeneously producing no uniformly drawn products.When the draw rate was increased,however,the draw stress increased,and a more uniform draw was achieved.Thus,uniformly drawn films were obtained at higher crosshead speeds corresponding to initial strain rates of 50–100/min.Furthermore,the ductility varied complexly with the draw rate.The maximum achieved DR increased with increasing the draw rate,reaching a maximum of ,4(corresponding to a strain of ,3in Fig.2)at a crosshead speed corresponding to an initial strain rate of 50/min.At yet higher draw rates,the ductility decreased again.Thus,the tensile drawing was made at a constant crosshead speed corresponding to an initial strain rate of 50/min.3.2.Crystal transformation during tensile drawing Fig.3shows WAXD photographs for a DR series prepared by tensile drawing of a highly oriented a film at a T d of 1708C and a constant crosshead speed corresponding to an initial strain rate of 50/min.The WAXD pattern of the initial sample showed many sharp reflections from highly oriented a crystals.However,upon drawing to a DR of 1.6,most of the sharp but weak reflections merged into the background and the remaining reflections showed a broad intensity distribution along the azimuthal direction.These observations reveal that the initially highly oriented a crystals were deformed and exhibited a broad orientation distribution around the fiber axis.Upon further drawing,the number of reflections from a crystals further decreased,and the remaining reflections became broad spots.Concurrently with these changes,the intensities of streaks along the equator and layer lines became stronger as the DR was increased,showing that significant paracrystalline disorder was introduced both along and perpendicularly to the chain axis [15,19,20].Although most of the broad reflections could be indexed on the basis of either the a -or b -form crystal,the appearance of such streaks suggested the formation of b crystals because such streaks are character-istic of b -form crystals [15,19].The crystal transformation can be followed by the relative intensity of the (003)b reflection from b crystals and the (0010)a reflection from a crystals recorded by WAXD meridional scans,as shown in Fig.4.The intensity of the (003)b reflection gradually increased with the DR at the expense of the intensity of the (0010)a reflection,showing a steady transformation of a crystals to b crystals.Since the degree of chain orientation for a crystals was slightly different from that for b crystals within a given sample,the relative amount of b crystals could not be directly correlated to the intensity ratio of the (0010)a and the (003)b reflections as previously done in the solid-state coextrusion of a PLLA film consisted of randomly oriented a crystals [20].The formation of b crystals was also evaluated from the FT-IR spectra that were corrected for the chain orientation according to Eq.(1).Fig.5shows the IR spectra for a draw ratio series prepared by drawing of a highly oriented a film at a T d of 1708C.To determine the relative amount of crystals formed within a drawn sample,the ratio of the absorption coefficients K ð912Þb =K ð923Þa for IR bands at 912and 923cm 21assigned to the CH 3rockingmodesFig.2.Stress/strain curves recorded at 1708C and different crosshead speeds corresponding to initial strain rates ð_g Þin the range of 0.5–100/min.K.Takahashi et al./Polymer 45(2004)4969–49764971[20,25]of b and a crystals,respectively,should be known.According to the Lambert–Beer law,absorbance A is given byA ¼log ðI 0=I Þ¼KdX cð2Þwhere I 0and I are the intensities of the incident beam and absorbed beam,respectively,K ;the absorption coefficient,d ;the sample thickness,and X c ;the crystallinity of a sample consisting of only a or b crystals.Therefore,the ratio of K ð912Þb =K ð923Þa is given by K ð912Þb =K ð923Þa¼A 0ð912Þb d ða ÞX c ða Þ=A 0ð923Þa d ðb ÞX c ðb Þð3Þwhere A 0ð923Þa and A 0ð912Þb are the total absorbances of the bands at 923and 912cm 21,respectively,d ða Þand d ðb Þ;the thicknesses of the samples consisting of only a and b crystals,respectively,and X c ða Þand X c ðb Þ;the crystal-linities of the a and b samples,respectively.The absorbances A 0ð923Þ0a s for a samples were measuredon two films;one consisting of highly oriented a crystals and one consisting of randomly oriented a crystals.The absorbance A 0ð912Þb for a b sample was measured on an extrudate prepared by solid-state coextrusion [20].By using the measured values of A 0;d ;and X c for the a and b samples,as shown in Table 1,the K ð912Þb =K ð923Þa was determined to be 1.1.Thus,the ratio of b crystals to the sum of a and b crystals within a drawn film can be calculated by A 0ð912Þb =½1:1A 0ð923Þa þA 0ð912Þbð4ÞFig.3.WAXD photographs for a draw ratio series prepared by the drawing of a highly oriented a film at a T d of 1708C and a constant crosshead speed corresponding to an initial strain rate of 50/min.Table 1IR absorbances for unoriented and oriented a samples at 923cm 21and an oriented b sample at 912cm 21Crystallinity ðX c ÞThickness ðd £106m ÞAbsorbance (A 0)Oriented a sample 0.7529 3.12(at 923cm 21)Unoriented a sample 0.4648 3.24(at 923cm 21)b sample0.51383.04(at 912cm 21)K.Takahashi et al./Polymer 45(2004)4969–49764972As the profile for each of the IR bands at 912and 923cm 21was well approximated by a Gaussian function,the observed IR spectra were resolved into the appropriate peaks at 912and 923cm 21assuming Gaussian functions that were determined from the samples consisting of only a crystals or b crystals,as shown in Fig.5.The relative amounts of b crystals estimated from the IR spectra are shown in Fig.6as a function of the DR.They increased almost linearly with the DR and approached ,0.9(90%)at a DR $3.5.3.3.Effect of draw temperatureFig.7shows the effect of the draw temperature,T d ;on the nominal stress/strain curves for the tensile drawing of a highly oriented a film recorded at a constant crosshead speed giving an initial strain rate of 50/min in the temperature range of 25–1808C.With increasing the T d ;the draw stress decreased and the ductility increased.More specifically,for the drawing at a lower T d #508C (glass transition temperature,T g ¼608C),the drawstressFig.4.WAXD meridional profiles for the draw ratio series shown in Fig.3.Fig.5.Polarized FT-IR spectra for the draw ratio series shown in Figs.3and 4.The spectra were corrected for the chain orientation.Observed (—)and decomposed spectra assuming Gaussian functions (---).Fig.6.Fractions of b crystals as a function of the draw ratio estimated from the IR spectra in Fig.5.Fig.7.Stress/strain curves recorded at a constant crosshead speedcorresponding to an initial strain rate ð_g Þof 50/min at different T 0ds in the range of room temperature to 1808C.K.Takahashi et al./Polymer 45(2004)4969–49764973increased rapidly with the strain until sample failure occurred.However,for the drawing at a higher T d of 100–1808C,the draw stress initially increased rapidly and then stayed almost constant at higher strains until failure occurred.The maximum DR achieved increased rapidly with a T d above the T g(608C)and reached a maximum of a DR of,4(corresponding to a strain of,3in Fig.7)at a T d of1708C,followed by a rapid decrease at yet higher T0d s: These results showed that the tensile drawing of a highly oriented afilm at a T d of1708C and a constant crosshead speed corresponding to an initial strain rate of50/min gave a uniform product with the highest DR of,4.To examine the effect of the T d on the crystal transformation,a highly oriented afilm was tensile-drawn at T0d s in the range of100–1808C to a constant DR of3, which was the highest DR commonly achievable at these T0d s:Fig.8shows WAXD photographs for a series of such samples.Upon drawing at a T d of1008C to a DR of3,most of the sharp and spotty reflections from the highly oriented a crystals of the starting sample(see Fig.1(b)(disappeared, and a few broad reflections continued to overlap with streaks on the equator and layer lines.These observations suggest that the crystal orientation was disturbed and that significant crystal disorders were induced both along and perpendicularly to the chain axis.With increasing the T d up to1408C,the broad reflections became slightly more circular whereas the streaks on the layer lines were significantly stronger.Most of the broad reflections could be indexed on the basis of either the a-or the b-form.For the drawing at the highest possible T d of1808C,the WAXD pattern consisted of a mixture of a number of sharp reflections from a crystals and a few broad reflections observed for the samples prepared at lower T0d s:This indicates that the efficiency of the crystal transformation from a to b crystals,defined by the ratio of b crystals to the sum of a and b crystals at a given DR,is lower at a high T d near the T m:In order to determine the effect of the T d on the formation of b crystals more quantitatively,the relative amounts of b crystals were determined from the FT-IR spectra for a series of samples drawn to a constant DR of3at different T0d s of 100–1808C.As shown in Fig.9,the fraction of b crystals increased with increasing the T d from a T d of1008C to a maximum at a T d of,1408C.At yet higher T0d s;it decreased rapidly with the T d:Our previous study[20]on the effect of drawing variables on the efficiency of the crystal transformation in solid-state extrusion of PLLA revealed that the transform-ation proceeded most efficiently for the extrusion around 1308C.Therefore,the combination of the presentfinding in tensile drawing and that in the previous solid-state extrusion suggests that the efficiency of the crystal transformation from a to b crystals upon drawing is primarily determined by the deformation temperature.3.4.Effect of draw stressIn a previous study[20]on the drawing of a PLLAfilm consisting of randomly oriented a crystals by solid-state coextrusion at1708C,it was found that the crystal transformation from a to b crystals proceeded with extrusion DR more rapidly for the extrusion at a higher extrusion pressure.As shown in Fig.2,the nominal draw stress increased with an increasing draw rate.Therefore,the effect of the draw stress on the efficiency of the crystal transformation was studied by drawing a highly orienteda Fig.8.WAXD photographs for a T d series drawn to a constant DR of3atdifferent T0d s in the range of100–1808C.Fig.9.Fractions of b crystals at a constant draw ratio of3as a function ofthe drawing temperature estimated from the IR spectra(A).K.Takahashi et al./Polymer45(2004)4969–49764974film at different draw rates and a T d of 1708C to a constant DR of 3.The DR of 3corresponds to the highest DR commonly achievable for the drawing at crosshead speeds,giving initial strain rates in the range of 20–100/min.When the crosshead speed was increased from 20,50,to 100/min,the true draw stress at a DR of 3(strain of 2),estimated by multiplying the nominal stress by the DR,increased from approximately 55,65,to 80MPa,respectively.The WAXD meridional profiles in Fig.10show that the intensity of the (003)b reflection increased with increasing the draw stress at the expense of the intensity of the (0010)a reflection.These results show that,when the tensile draw was made at a constant T d but at different draw rates,the crystal transformation proceeded with DR more efficiently for the draw at a higher draw rate and,hence,a higher draw stress.As have been discussed,there is an optimum T d of ,1408C at which the efficiency of crystal transformation is the highest for both tensile drawing and solid-state extrusion.As seen in Fig.10,for the drawing at a given T d ;the efficiency was higher for the drawing at a higher draw rate and,hence,at a higher draw stress suggesting,that the crystal transformation is enhanced by a higher draw stress.For the draw at a given draw rate,indeed,the true draw stress at a given strain increased steadily with decreasing the T d (Fig.7),and the efficiency of the crystal transformation increased rapidly with decreasing the T dfrom 180to 1408C.However,at yet lower T 0d s ;the efficiency of the crystal transformation decreased withdecreasing the T d even though the draw stress increased steadily with decreasing the T d :These facts suggest that there is another factor,which has an opposite effect to that of the draw stress on the crystal transformation when the T d is changed.When the T d is lowered,the crystals likely become harder,and the crystal transformation may be suppressed,as suggested by the fact that the ductility decreased with lowering the T d (Fig.7).As a result of the combined effects of the draw stress,which increases with decreasing the T d and enhances the crystal transformation,and the crystal hardening,which proceeds with decreasing the T d and suppresses the transformation,the efficiency of the crystal transformation became the highest at a T d of ,1408C.4.ConclusionA PLLA film consisting of highly oriented a crystals was tensile-drawn at a T d of 25–1808C and constant crosshead speeds corresponding to the initial strain rates of 0.5–100/min.To determine the effects of the DR,T d ;and draw stress on the crystal transformation from the a -to the b -form,the drawn products were characterized by WAXD and polarized FT-IR spectroscopy.At the initial stage of drawing,the highly oriented a crystals within the starting sample were inclined to the draw direction,and,upon further drawing,they progressively transformed into oriented b crystals.These observations suggest that macroscopically extensional deformation for tensile draw-ing proceeded by microscopically shear deformation.The crystal transformation,evaluated by the ratio of b crystals to the sum of a and b crystals at a given DR that was determined from the IR absorbances at a 912cm 21band for b crystals and a 923cm 21band for a crystals,was higher for the drawing at a higher draw stress when compared at a given T d :However,there was a T d of ,1408C,at which the crystal transformation proceeded most efficiently with the DR even though the draw stress steadily increased with decreasing the T d :This finding suggests that the efficiency of the crystal transformation is controlled by two factors of the draw stress and crystal hardening,which had opposite effects when the T d was changed.However,an oriented sample consisting predominantly of b crystals was obtainedby tensile draw in a wide range of T 0ds as a result of the combined effects of T d and DR on the crystal transformation and the ductility increase with the T d :AcknowledgementsThis work was partly supported by the Grant-in-Aid from Office of Technology Transfer,Japan Science and Tech-nologyCorporation.Fig.10.WAXD meridional profiles for samples with a DR of 3prepared at a T d of 1708C but at different crosshead speeds corresponding to the initial strain rates of 20,50,and 100/min.The true draw stresses at a DR of 3for different draw rates are shown below the strain rates.The decomposition of the observed profiles into three peaks was made by assuming a symmetrical function consisting of Gaussian and Cauchy profiles for each peak.K.Takahashi et al./Polymer 45(2004)4969–49764975References[1]Kronenthat RL,Oser Z,Martin E,editors.Polymers in medicine andsurgery.Polymer 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