Inclusion-controlled fatigue properties of 1800 MPA-class spring steels

Designation:F432–04Standard Specification forRoof and Rock Bolts and Accessories1This standard is issued under thefixed designation F432;the number immediately following the designation indicates the year of original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.A superscript epsilon(e)indicates an editorial change since the last revision or reapproval.1.Scope*1.1This specification covers the chemical,mechanical,and dimensional requirements for roof and rock bolts and accesso-ries.Addressed in this specification are double-end threaded and slotted steel bars;fully grouted bolts and threaded bars; mechanical anchorage devices used for point anchorage appli-cations;roof truss systems;partially grouted deformed bolts; formable anchorage devices;and other frictional anchorage devices.All of these products represent various designs used for ground support systems.This specification can be revised to address new technologies.1.2The values stated in inch-pound units are to be regarded as the standard.The values given in parentheses are for information only.1.3This hazard statement applies only to Section10,Test Methods of this specification.This standard does not purport to address the safety concerns,if any,associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.2.Referenced Documents2.1ASTM Standards:2A29/A29M Specification for Steel Bars,Carbon and Alloy, Hot-Wrought,General Requirements forA47/A47M Specification for Ferritic Malleable Iron Cast-ingsA194/A194M Specification for Carbon and Alloy Steel Nuts for Bolts for High-Pressure or High-Temperature Service,or BothA220Specification for Pearlitic Malleable IronA370Test Methods and Definitions for Mechanical Testing of Steel ProductsA536Specification for Ductile Iron CastingsA563Specification for Carbon and Alloy Steel NutsA568/A568M Specification for Steel,Sheet,Carbon,and High-Strength,Low-Alloy,Hot-Rolled and Cold-Rolled, General Requirements forA615/A615M Specification for Deformed and Plain Billet-Steel Bars for Concrete ReinforcementA751Test Methods,Practices,and Terminology for Chemical Analysis of Steel ProductsD1248Specification for Polyethylene Plastics Extrusion Materials for Wire CableF436Specification for Hardened Steel WashersF606Test Methods for Determining the Mechanical Prop-erties of Externally and Internally Threaded Fasteners, Washers,and Rivets2.2ASME Standards:3B1.1Unified Screw ThreadsB1.3M Screw Thread Gaging Systems for Dimensional Acceptability—Inch and Metric Screw ThreadsB18.2.2Square and Hex Nuts3.Terminology3.1Definitions:3.1.1bearing plates,plate washers,mine roof plates—plates that serve to distribute the load from the exposed end of the bolt or threaded bar to the rock face or intermediate member.3.1.1.1header plates—large rectangular bearing plates, usually6in.(152mm)wide by16to18in.(406.4to457.2 mm)long,or any other shape with an equivalent area,used in substitution for wooden header blocks for wider distribution of the bolt load than is possible with standard bearing plates. 3.1.2bendable bolts—bolts furnished with an altered sec-tion at some location,to be specified by the customer,at which the bar will bend.1This specification is under the jurisdiction of ASTM Committee F16on Fasteners and is the direct responsibility of Subcommittee F16.02on Steel Bolts, Nuts,Rivets,and Washers.Current edition approved Aug.1,2004.Published August2004.Originally approved st previous edition approved in2001as F432–95(2001).2For referenced ASTM standards,visit the ASTM website,,or contact ASTM Customer Service at service@.For Annual Book of ASTMStandards volume information,refer to the standard’s Document Summary page on the ASTM website.3Available from American Society of Mechanical Engineers(ASME),ASME International Headquarters,Three Park Ave.,New York,NY10016-5990.1*A Summary of Changes section appears at the end of this standard. Copyright©ASTM International,100Barr Harbor Drive,PO Box C700,West Conshohocken,PA19428-2959,United States.3.1.2.1Discussion—Bending is necessary to permit instal-lation of bars longer than the mine opening height.This altered section may be produced by hot or cold forging,or by shearing, sawing,trimming,machining,grinding,or a combination of these processes.3.1.3beveled washers—washers whose faces are at an angle permitting a headed bolt or threaded bar to be installed at a slight angle to the rock face and yet maintained the face of the bolt head perpendicular to the bolt axis.3.1.4chemical anchors—chemical materials that provide anchorage between the bolt or bar and the drilled hole.3.1.5expansion shells—anchorage devices that expand to grip the sides of a drilled hole mechanically and transfer load from the location of the anchor to the bar or bolt.3.1.6extensions—threaded bars used to extend the length of threaded or threaded slotted bars.3.1.7formable anchorage devices—any roof support de-vices that provide anchorage through some means of physical interference and engagement of the surface of a bar or bolt with any formable material,other than chemical grout,in a bore-hole.3.1.8frictional anchorage devices—roof support devices that are designed so that the holding force acts over the full contact length.3.1.9fully grouted bolts and threaded bars—deformed bars or plain bars used with full-length grouting and having special deformations or other design features to provide interlocking between the steel and the grout.3.1.10hardened washers—washers that have been hard-ened by heat treatment to provide consistency to the torque tension relation necessary to control installation tension of bolts and threaded bars.3.1.11minimum non-seizure load(MNSL)—the load level in pounds through which bolt/plug thread seizure must not occur.3.1.12minimum ultimate load(MUL)—the load level in pounds through which bolt/plug thread failure must not occur.3.1.13rollers,cams—moving devices that,when used with internally threaded cylinders containing external tapered slots, provide expansion to grip the sides of a drilled hole mechani-cally and transfer load from the location of the anchor to the bar or bolt.3.1.14roof and rock bolts—headed hot-rolled bars with cold-rolled or machine-cut threads at the end,to be used with anchorage devices to hold up mine roofs,hold back walls,or hold down equipment or foundations.3.1.15roof truss system—a roof support system incorporat-ing bolts that are joined together by crossmember(s)that is (are)tensioned by design.3.1.16spherical washers or seats—washers that areflat on one side and have a spherical face on the other side.The combination of spherical washer together with a depression in the bearing plate produces a ball-and-socket joint permitting bolts to be installed at a slight angle to the rock face while still maintaining the face of the bolt head perpendicular to the bolt axis.3.1.17tapered wedges—plain wedges that provide the expansion for threaded slotted bars.3.1.18tension nuts—nuts that are intended to induce and maintain tension in a bolt.3.1.19threaded bars—bars that are used with a nut on one end and an anchorage device on the other.They are used in a manner similar to the bolts described in3.1.14.3.1.20threaded couplings—couplings used to permit the assembly of additional externally threaded items.3.1.21threaded slotted bars—bars threaded at one end each with a forged,burned,or sawed slot at the other,into which a tapered wedge can be inserted.When each assembly is driven into a bottomed hole,the wedge spreads the slot and an anchorage is produced.3.1.22threaded tapered plugs—threaded wedge that ex-pands the expansion shell by the movement of the threaded plug within the shell as tightening progresses.4.Ordering Information4.1Orders for material under this specification shall include at least the following information:4.1.1Quantity(number of pieces),4.1.2Name of product together with description of acces-sories,4.1.3Dimensions,4.1.4ASTM designation and year of issue,including strength grade,4.1.5Special requirements,if any,including packaging and thread protection instructions,and4.1.6Certifications,if required.4.2The products covered by this specification are currently produced by many manufacturers to a wide variety of designs. It is necessary for the user and the manufacturer to establish the requirements of the individual installation and to agree as to the type of assembly to be employed.See Annex A1and Appendix X1for additional information.5.Manufacturing Processes5.1Materials for Bolts,Extensions,and Threaded or Threaded Slotted Bars:5.1.1Steel shall conform to the requirements shown in Table1and in Specification A29/A29M for plain bars or TABLE1Chemical RequirementsProduct Carbon,max,%Sulfur,max,%Phosphorus,max,%Heat Product Heat Product Heat Product Bolts,threadedbars,and threadedslotted bars A0.750.790.13B0.0500.058 Steel tapered wedges0.800.840.13B0.0500.058 Hardened spherical,flat,or beveledwashers0.800.840.0500.0580.0500.058 Spherical or beveledwashers0.800.840.0500.0580.0500.058 Bearing and headerplates 1.00 1.040.0500.0580.0500.058 Steel threaded taperedplugs0.600.640.13B0.0500.058 Steel expansion shells0.300.330.0500.0580.0500.058 A Bars furnished in accordance with Specification A615/A615M may be substitutedfor these requirements.B Check analysis for sulfur if a resulfurized steel is not technically appropriate.Specification A615/A615M for plain or deformed bars unless otherwise specified.5.1.1.1Threaded slotted bars may have the slot produced by forging,burning,or sawing.Burned slots of Grades55and75 threaded slotted bars must have the slotted end normalized by heating to a minimum of1600°F(870°C)and air coolingsubsequent to burning.5.1.1.2Threads on bolts or threaded bars may be cold rolled or machine cut on the hot-rolled bars.5.2Materials for Tapered Wedges for Use With Threaded Slotted Bars:5.2.1Malleable iron casting shall conform to Specification A47/A47M.5.2.2Pearlitic malleable iron castings shall conform to Specification A220,Grades45006or50005.5.2.3Steel shall conform to the requirements shown in Table1.5.3Materials for Expansion Shells:5.3.1Malleable iron castings shall conform to Specification A47/A47M.5.3.2Steel shall conform to the requirements shown in Table1.5.3.3Ductile iron castings shall conform to Specification A536,Grades60-40-18.5.4Materials for threaded tapered plugs used with expan-sion shells shall conform to the test specifications in10.8. 5.5Materials for Bearing and Header Plates,Also Known As Plate Washers or Mine Roof Plates:5.5.1Steel shall conform to the requirements shown in Table1.5.5.1.1Bearing and header plates may be strengthened by cold forming or may be hardened by quenching in a liquid medium from above the austenitizing temperature and temper-ing at a temperature of not less than650°F(345°C).5.6Materials for Spherical,Flat,or Beveled Hardened Washers:5.6.1Steel shall conform to the requirements shown in Table1.5.6.1.1Hardened steel washers shall be through hardened by quenching in a liquid medium from above the austenitizing temperature and tempering at a temperature of not less than 650°F(345°C).Case-hardened washers are not permitted. 5.7Materials for Spherical or Beveled Washers:5.7.1Malleable iron castings shall conform to Specification A47/A47M.5.7.2Pearlitic malleable iron castings shall conform to Specification A220,Grades45006,50005,or60004.5.7.3Steel shall conform to the requirements shown in Table1.5.8Nuts shall be in accordance with Specifications A194/ A194M or A563.Appropriate nuts for each grade of threaded bar are shown in Table2.Higher strength nuts conforming to Specifications A194/A194M or A563may be substituted. When specified on the order or contract,nuts with external dimensions of nominal3⁄4-in.heavy hex or heavy square size may be supplied with5⁄8-in.threads for use with5⁄8-in.threaded bars.5.9Chemical grouting materials are covered in Annex A3of this specification.5.10Materials for threaded couplings shall be selected by the manufacturer to ensure compliance with7.6and8.7.5.11Materials for Bolts and Threaded Bars for Use in Grouted Systems—Plain or deformed steel bars shall conform to Table1or Specification A615/A615M.5.12Materials for Frictional Anchorage Devices—Sheet steel shall conform to Specification A568/A568M.5.13Components of roof truss systems shall be manufac-tured in accordance with the appropriate paragraph(s)of Section5of this specification.5.14Materials for Formable Anchors:5.14.1Materials for formable anchor tubes are as follows: 5.14.1.1Polyethylenes used for formable anchor tubes shall conform to ASTM D1248Classification Type III,Class A or B,Category5.N OTE1—All shapes,compositions,and properties of formable anchor materials are not covered by this specifiers must ensure that the formable anchor material offered is suitable for its intended use.6.Chemical Composition6.1Materials used for bolts,threaded bars,threaded slotted bars,spherical,flat,or beveled washers,threaded tapered plugs,tapered wedges,expansion shells,bearing plates and roof truss components shall be as specified in Table1and Section5.6.2Materials for all cast or wrought metallic items other than those covered in6.1shall conform to the requirements as specified in Section5.6.3Individual heats of steel or cast iron are not identified in any of thefinished products.6.4Chemical analyses for steel products shall be performed in accordance with Test Methods,Practices,and Terminology A751.6.5Materials for formable anchors shall conform to the requirements,if applicable,specified in Section5.6.6Chemical analyses shall be performed in accordance with Test Methods,Practices,and Terminology A751.7.Mechanical Properties7.1Mechanical properties of steel bars,for the manufacture of bolts,threaded bars,or threaded slotted bars shall be as specified in Table3for the required grade.7.2Mechanical properties of steel bolts,threaded bars,and threaded slotted bars whose slots have been produced without material removal shall be as specified in Table4for the required grade.7.3Expansion shells,threaded tapered plugs,tapered wedges,and spherical washers shall conform to the applicable specification of Section5and shall successfully perform the required purpose as described in Annex A1.TABLE2Appropriate NutsBolt,Threaded Bar,or Threaded SlottedBar GradeNut Specification30(regular strength)A194,Grade1;A563,Grade B55(high strength)A194,Grade1;A563,Grade B75(extra high strength)A194,Grade2;A563,Grade C7.4Bearing plates and header plates that are strengthened by quenching and tempering shall have a maximum hardness of 45HRC.7.4.1Bearing plates and header plates shall be provided in 10000-lbf (44.5-kN)grade increments.The minimum grade rating permitted shall be 20000lbf (89.0kN).7.5Hardened washers shall have a hardness range from 35to 45HRC.7.6Threaded couplings must be capable of developing the actual yield and tensile values of the bolt,threaded bar,or threaded slotted bar with which they are to be used.7.7Extensions must be in accordance with 7.1and 7.2for the grade of item specified.7.8Mechanical properties for bolts and threaded bars for use in grouted systems shall be as specified in Table 3for plain bars;and Table 3or Specification A 615/A 615M for deformed bars.Bolts and threaded bars made from plain material must contain some design feature to provide interlocking between the steel and the grout.These items can be supplied threaded or headed.7.9Threaded slotted bars whose slots have been produced by burning shall be heat treated by normalizing in accordance with 5.1.1.The normalizing heat treatment and the removal of material from the slot,whether it be by burning or sawing,will result in lower test values.When either the burning or sawing or other methods involving metal removal are used,the mechanical properties of threaded slotted bolts shall be as specified in Table 5.7.10Threaded tapered plugs for expansion anchors must be capable of withstanding the minimum nonseizure load (MNSL)and minimum ultimate load (MUL),in accordance with Table 6.7.11Tension nuts must be capable of withstanding the ultimate tensile strength of the bolt or rebar of the highest grade with which they are to be used.7.12The mechanical properties of components of roof truss systems shall be in accordance with the appropriate para-graph(s)of this section.7.12.1Truss brackets shall be provided in 10000-lbf (44.5-kN)grade increments.7.13Formable anchor materials shall conform to the appli-cable specifications of Section 5.8.Dimensions,Mass,and Permissible Variations8.1Threaded bolts shall conform to the dimensions shown in Fig.1.8.1.1Deformed bar bolts are bars that have been forged to produce one of the standard heads described in Fig.1.8.2Threaded and threaded slotted bars shall conform to the dimensions shown in Fig.2.8.3Thread Requirements :N OTE 2—Thread size variations can be expected due to bar diameter and out-of-round variations.These special requirements reflect practices for external and internal threads that have been found to provide adequate strength and interchangeability.8.3.1External threads shall be in accordance with ASME B 1.1UNC 1A except that the minimum pitch diameter has been reduced by 0.003in.(0.08mm)and the minimum major diameter has been reduced 0.010in.(0.25mm)to reflect the normal variations expected on hot-rolled bars due to the combined effect of bar diameter and out-of-round rmation on this increased tolerance is described in Note 3.The modified requirements are listed in Table 7.N OTE 3—External threads that are to be used with threaded tapered plugs in expansion anchors are permitted to have somewhat increased pitch and major diameter tolerance.As bolt load is increased,the tendency for thread failure through nut diametrical expansion normally increases;however,in the case of threaded tapered plugs,increased load is accompanied by an increasing compression of the internal threads onto the external threads.This compensation for decreased major diameter is further augmented by the length of engagement which is longer than for standard nuts.Nuts to be used with threaded bars and threaded slotted bars shall be selected to provide adequate strength under these thread condi-tions.8.3.2Internal threads in threaded tapered plugs and threaded couplings shall be in accordance with ASME B 1.1UNC 1B except that the threads shall be tapped oversize.This oversize is an increase in the pitch diameter of 0.003in.(0.08mm)to allow for handling damage on the external thread and dirt and long engagement in the internal thread.The maximum minor diameters are standard 1B for 11⁄2to 3diameter length of engagement.The modified requirements are listed in Table 7.8.3.3Internal threads in nuts shall be tapped standard UNC 2B size in accordance with ASME.1or may be tapped oversize in accordance with 8.3.2with agreement of producer and purchaser.8.3.4Gaging of threads shall be performed in accordance with System 21,ASME B 1.3M.Pitch diameter and thread crest diameter limits are specified in Table 7.8.3.5Threaded tapered plugs shall have a tapped length at least equal to one times the nominal bolt diameter with which they are to be used.8.3.6Threaded couplings shall have a tapped length at least equal to two times the nominal bolt diameter with which they are to be used.8.4Round and square hardened washers shall be as shown in Fig.3.8.4.1There are two types of hardened flat washers avail-able.Type 1is to be furnished unless otherwise specified.8.4.1.1Type 1is either circular or square as shown in Fig.3.It is designed for use with plate washers containing 13⁄8-in.(35-mm)holes,but may be used for all smaller hole sizes.TABLE 3Mechanical Properties of Steel Bars for the Manufacture of Bolts,Threaded Bars,and Threaded SlottedBars ABGradeNominal Diameter,in.C Yield Point min,psi (MPa)Tensile Strength min,psi (MPa)Elongation in 8in.or 200mm Minimum,%40D 3⁄4–11⁄240000(276)70000(483)12555⁄8–11⁄255000(379)85000(586)1260D 5⁄8–11⁄260000(414)90000(621)9755⁄8–11⁄275000(517)100000(688)81005⁄8–11⁄2100000(689)125000(862)6A Test of bars shall be performed full size.BHigher grades would be produced in 20000-psi increments.The minimum tensile strength shall be 25000psi above the minimum yield strength.The minimum elongation shall be 4%for all grades above 100.CActual bar diameters are somewhat less than nominal,especially when roll threading methods are employed.DGrade 40and 60only apply to deformed bar.8.4.1.2Type2is the hardenedflat washer in accordance with Specification F436.It may be used only when sufficient clearance is available between the threaded-bar or threaded-rolled-bar body diameter near the head and the washer hole. This washer is not suitable for use with plate washers that contain holes that are more than3⁄8in.(9.5mm)greater in diameter than the nominal bolt diameter.8.5Bearing and header plates may be of any thickness that successfully meets the test requirements in accordance with 10.4.The maximum hole size for use with bolts up to3⁄4-in. nominal diameter shall be13⁄8in.(35mm)except that hole size may be11⁄2in.(38mm)when spherical washers or seats are used.Tolerance on hole diameter shall be−0,1⁄8in.(−0,+3.2 mm).Bearing plates for direct bearing applications shall be6 by6in.(152by152mm)with tolerances for length and width of61⁄rger bearing plates may be furnished,dimensionsTABLE4Load Support Requirements of Steel Bolts,Threaded Bars,(see Annex A2)Threaded Deformed Bars, and Threaded Slotted Bars Whose Slot Has Been Produced Without Metal Removal AN=NewtonkN=kiloNewton1lb=4.448N or0.004448kNNominal Diameter (in.)/Thread /in.ThreadStress Area,in.2(mm2)Grade40B5560B75100 Yield lbs(kN)CUltimate lbs(kN)CYield lbs(kN)CUltimate lbs(kN)CYield lbs(kN)CUltimate lbs(kN)CYield lbs(kN)CUltimate lbs(kN)CYield lbs(kN)CUltimate lbs(kN)C5⁄8–110.226(1.46)D D12400(55.16)19200(85.4)13600(60.50)20300(90.30)17000(75.6)22600(100.5)22600(100.5)26300(130.8)3⁄4–100.334(2.65)13400(59.60)23400(104.08)18400(81.8)28400(126.3)20000(89.0)30100(133.9)25100(111.6)33400(148.6)33400(146.6)41800(193.5)7⁄8–90.462(2.96)18500(82.3)32300(143.7)25400(113.0)39300(174.8)27700(123.2)41600(185.0)34700(154.3)46200(205.5)46200(205.5)57800(267.3)1–80.606(3.91)24200(107.6)42400(188.6)33300(148.1)51500(229.0)36400(161.9)54500(242.4)45500(202.4)60600(269.5)60600(269.5)75800(350.5)11⁄6–70.763(4.92)30500(135.7)53400(237.5)42000(186.8)64900(286.7)45800(203.7)68700(305.6)57200(254.4)76300(339.4)76300(339.4)95400(441.2)11⁄4–70.969(6.25)38800(172.6)67800(301.6)53300(237.1)82400(366.5)58100(258.4)87200(387.9)72700(323.4)96900(431.0)96900(431.0)121100(560.4)13⁄8–6 1.155(7.45)46200(205.5)80900(359.8)63500(282.4)96200(436.8)69300(308.2)104000(462.6)86600(385.2)115500(513.7)115500(513.7)144400(668.1)11⁄2–6 1.405(9.06)56200(250.0)98400(437.7)77300(343.8)119400(531.1)84300(375.0)126500(562.7)105400(468.8)140500(624.9)140500(624.9)175600(814.6)A Tests of bolts and threaded bars shall be performed using full-diameter products.B Information for Gr40and60only applies to deformed bars.C Required yield and tensile loads shown are calculated by multiplying thread stress areas times the yield point and tensile strength values shown in Table3.Thread stress area is calculated from the mean root and pitch diameters of adrenal threads as follows:A s50.7854S D20.9743n D2where:A s=stress area,in.2D=nominal diameter,in.,andn=number of threads per inch.D5⁄8in.Gr40products are not covered.TABLE5Load Support Requirements for Threaded Slotted BarsWhose Slot Has Been Produced by Methods Involving MetalRemoval ANominal Diameter, in.Thread StressArea,min,in.2(mm2)Grade55Yield Load,min,lbf(kN)BUltimate TensileLoad,min,lbf(kN)B10.606(3.91)30000(133.3)46400(206.2) 11⁄40.969(6.25)48000(213.4)74200(329.9) 13⁄8 1.155(7.45)57200(254.2)88400(393.1) 11⁄2 1.405(9.06)69600(309.4)107500(478.0) A Tests of bolts,threaded bars,and threaded slotted bars shall be performed using full-diameter products.B Required yield and tensile loads shown are calculated by multiplying thread stress areas times the yield point and tensile strength values shown in Table2. Thread stress area is calculated from the mean of the mean root and pitch diameters of Class3external threads as follows:A s50.7854S D20.9743n D2where:A s=stress area,in.2D=nominal diameter,in.,andn=number of threads per inch.TABLE6Plug Grade Rating SystemNominalDiameter,in.Grade1Grade2Grade3Grade4 MNSL A MUL B MNSL A MUL B MNSL A MUL B MNSL A MUL B 1⁄27.014.210.717.013.519.916.322.7 5⁄812.422.617.027.121.531.626.036.1 3⁄418.433.425.1†40.131.746.8†38.453.4†7⁄825.4†46.234.755.440.064.740.073.9 133.360.640.072.740.084.840.096.9 11⁄840.076.340.091.640.0106.840.0122.0 11⁄440.096.940.0116.340.0135.740.0155.0†13⁄840.0115.5†40.0138.640.0161.740.0184.8 11⁄240.0140.5†40.0168.640.0196.740.0224.8A MNSL—Minimum Non-Seizure Load(1000lb).B MUL—Minimum Ultimate Load(1000lb).†Editorially corrected.and tolerances to be by agreement between the producer and the purchaser.Smaller bearing plates may be used in conjunc-tion with steel channels,with other accessories,or in hard rock areas by agreement between the producer and the purchaser.Header plates are typically 6in.(152mm)wide by 16to 18in.(406.4to 457.2mm)long,or any other shape with an equivalent area.8.6Bearing and header plates used with frictional anchor-age devices shall meet the test requirements in 10.4.TheholeNominal Bolt Size,5⁄8to 1in.(Note 1)H Head Height,min.,in.(mm)0.476(12.09)F Head Across Flats,in.(mm) 1.088to 1.125(27.64to 28.58)G Head Across Corners,in.(mm) 1.425to 1.591(36.19to 40.41)EBody diameter is controlled by the roll threading operation.Note 1—When specified by the customer on the order or contract,the 5⁄8-in.diameter bolt may be supplied at:H—0.400(10.16)F—0.906to 0.938(23.01to 23.83)G—1.244to 1.326(31.60to 33.68)Note 2—When specified by the customer on the order or contract,a shoulder,collar,or swell equal to the body diameter of a 3⁄4-in.diameter bolt may be applied under the head of a 5⁄8-in.diameter bolt for a length of approximately 3⁄16in.Note 3—Pinched ears may be provided to support the expansion shell during installation.Note 4—Bolt head may have depressed center.Note 5—See Table 7for head markings.Note 6—See Paragraph 8.3.1for threads.Note 7—Forging flash is permitted.FIG.1Roof and RockBoltsN OTE 1—Pinched ears may be provided to support the expansion shell during installation.N OTE 2—See 8.3.1for threads.N OTE 3—E Body diameter is established by the method of threading.N OTE 4—Body diameter is controlled by the roll threading operation.FIG.2Threaded Bars and Slotted ThreadedBars。

一
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摘
要
通过 Ｕ Ｆ２ ０ Ｓ －０ ０超声波疲 劳试验机研究 了 ５ ０ｋ ０ ｇ真空 感应 炉 ＋电渣重 熔 冶炼 的２０ ０ＭＰ ０ ａ高强度 钢
杂物处应力场强度 因子 Ａ Ｉ Ｋ 的减小 ， 钢的疲劳寿命 Ⅳ 增加 。 ｆ 关键词 高强 度钢 非金 属夹杂物 超高周疲 劳 破坏行为
Ｆａ ｌ ｅ Ｂｅ ｖ ｏ ｆＵｌｒ — ｉ ｈ Ｃｙ ｌ ｔｇ ｆ ｉ ｕｒ ｈａ ｉ ｒ ｏ ｔ ａ ｈ ｇ ｃ ｅ Ｆａ ｉ ｕｅ ｏ ａ ２ ０ ０ Ｍ Ｐａ Ｇ ｒ ｄ ｇ ｔ ｅ ｔ ｔ ｅ ０ ａ ｅ Ｈｉ ｈ Ｓ ｒ ｎｇ ｈ Ｓ ｅ ｌ

钢材专业术语------ADDITIONS:Materials, typically alloy elements, added to molten steel to produce the chemical specifications for the desired steel grade.ALLOY:A substance that has metallic properties and is comprised of two or more chemical elements of which at least one is a metal.ALLOY STEEL:Steel containing one or more alloying element. Steel is classified as alloy when the maximum content of alloying elements exceeds one or more of the following: manganese 1.65%, silicon 0.60%, copper 0.60%.ALLOYING ELEMENTS:Chemical elements added for improving the properties of the finished products. Some alloying elements are nickel, chromium, manganese, molybdenum, and silicon.ANNEALING:A process involving heating and cooling, usually applied to induce softening of steel. The term also refers to treatments intended to alter mechanical or physical properties, produce a definite microstructure or remove gasses.ARGON SHROUD:A procedure using argon gas to shield molten steel from oxygen as it is teemed from the ladle.ARGON STIRRING:An inert gas introduced through a nozzle to stir molten steel to promote chemical and temperature homogenization and float out inclusions.AUSTENITE:High-temperature solid form of steel with face-centered cubic crystal structure.-----BILLET:A semi-finished piece of steel that results from rolling an ingot or a bloom. It may be square but is never more than twice as wide as thick. Its cross-sectional area is usually not more than 36 square inches.BLOOM:A semi finished piece of steel resulting from the rolling or forging of an ingot. A bloom is square or not more than twice as wide as thick and usually not less than 36 square inches in cross-sectional area.BLOOM SHEAR:A shear used to cut a rolled ingot into shorter bloom lengths or to cut off the ends of a bloom.BLOWHOLE:An internal cavity in steel produced by gases during the solidification of the metal.BOTTOM POURING:The process of pouring ingots using a refractory runner system to fill them from the bottom of the ingot molds.BREAKOUT:Liquid steel flowing through the shell of a ladle or EAF.BRINNEL HARDNESS:A hardness test commonly used for soft steel and metals which measures diameter of an indentation made by a steel ball under a given load.BUTT:An unfinished or incomplete ingot.-----CARBIDE:A compound of iron (or other element) and carbon in steel, forming a very hard, nonmetallic substance (Fe3C). Fe3C is also called cementite.CASTING:Pouring molten metal into a mold, or the metal object (i.e., ingot) produced by such pouring.CASTING POWDER:A powder applied to the inside of a mold before teeming to prevent the metal from sticking to the mold.CHARGE:To load a furnace with scrap and flux prior to melting, or to load a soaking pit with ingots for reheating.CHEMISTRY:The chemical constituents of a heat of steel.COLD WORKING:Rolling or drawing semi-finished steel products to provide higher physical properties or better surfaces than can be produced by hot-working.CONTINUOUS CASTER:A machine used to continuously produce blooms from molten steel with no interruptions or intermediate operations.CREEP:Failure of a metal caused by gradual elongation due to constant stress.CRYSTAL:Physically uniform solids composed of atoms bonded together in a definite geometrical pattern or structure.CRITICAL TEMPERATURE:The temperature at which a steel transforms one crystal structure into another because of atom rearrangement. CONTINUOUS THERMAL TREATMENT FACILITY (CTTF):Facility at Timken's Gambrinus Steel Plant that includes austenitizing and tempering furnaces, straightener, carbide saw, cooling beds, and transfer tables that are used for heat treatment of steel.-----D back to top-----DECARBURIZATION:Loss of carbon at the steel surface caused by poor atmosphere control.DEGASSING:Lowering the hydrogen and oxygen content of the steel by placing the molten steel in a vacuum.DENDRITES:Crystals that form in a tree-like pattern during solidification.DEOXIDIZE:Removal of oxygen from steel.DIFFUSION:Movement of atoms in solids. Heat provides the energy for atom movement.DRAW:To empty a soaking pit one ingot at a time to feed rolling operations (FSP), or to pull steel (usually cold) through a die to change its dimensions and mechanical properties.DUCTILITY:Ability to undergo permanent changes of shape without rupturing.-----E back to top-----ELASTIC DEFORMATION:Temporary distortion of a material under the action of applied stresses.ELECTRIC ARC FURNACE (EAF):A refractory-lined steel vessel used to melt steel. An electric arc generates the heat.ELECTRODE:A carbon (graphite) rod that carries electricity to melt the scrap in an EAF.ENDOTHERMIC:A chemical change in which there is absorption of heat.ETCH:A steel sample treated with acid to reveal its microstructure; used to visually check conditions such as porosity, large inclusions, or other nonconformities.EXOTHERMIC:A chemical change in which there is liberation of heat.-----F back to top-----FATIGUE:Failure of metal due to repeated cyclic stressing.FETTLE:To prepare a furnace for charging and melting by repairing eroded areas of the refractory.FLASH STICKER:An ingot that will not separate from the mold because of leakage thatoccurred between the mold and the mold stool.FLUX:A slag-making ingredient or the increased fluidity of slag.FORGING:Forming hot metal in the desired shape by means of hammering or pressing.FREEZE:Solidify molten steel as it cools from the liquid to solid state.-----G back to top-----GRADE:Classification of steel based on carbon content or mechanical properties.GRAIN:Orderly arrangement of atoms or crystal structure. Individual crystal of a microstructure.GRINDING:Method of conditioning steel by removing surface flaws using a power-driven grinding wheel. -----H back to top-----HARDENABILITY:The depth and distribution of hardness below the surface of steel.HARDENING:The process of increasing the hardness of steel through controlled heating and cooling.HARDNESS:Resistance to indentation.HEAT:An individual batch of metal as it is treated in a furnace.HEAT TREATMENT:A combination of heating and cooling operations applied to a metal or alloy to obtain desired microstructure conditions or properties.HEEL:Molten steel left in the furnace after tapping.HOT TOP:An insulated reservoir on top of an ingot mold that retains heat and holds excess molten metal that is drawn into the ingot as it shrinks.HOT TOP COMPOUND:Insulating material placed on top of the molten metal after the mold is filled.HOT WORKING:Plastic deformation of metal at specific temperature and rate to prevent strain hardening from occurring.-----I back to top-----IMMERSION SAMPLE:Sample taken directly from the molten steel for chemical analysis.IMPACT TEST:A test to determine energy absorption obtained by fracturing a test bar at high velocity.INCLUSION:Particles of nonmetallic impurities that are mechanically held in steel during solidification, usually oxides, sulphides, and silicates.INGOT:Steel, formerly in a molten state, transferred to an ingot mold to solidify.INGOT MOLD:A form into which molten steel is poured to solidify.IRON:A pure metal that serves as the basis for steel, cast iron and stainless steel. Iron is relatively weak and soft when in its pure form.-----J back to top-----JOMINY TEST:Hardenability test usually performed on alloy steels.-----K back to top-----KILLED STEEL:Steel that is deoxidized with a strong deoxidizing agent, such as silicon or aluminum. Reducing the oxygen content minimizes chemical reaction between carbon and oxygen during solidification.-----L back to top-----LADLE:A vessel for receiving and handling liquid steel. It is constructed of a refractory-lined steel shell.LADLE REFINING SYSTEM (LRS):System where alloys are added to meet exact chemistries, gases are removed by vacuum, and argon bubbles stir the molten mixture to remove impurities and mix the alloying elements. Arc heating maintains steel temperature.LOW-ALLOY STEEL:Steel containing up to 5% alloying elements other than carbon.-----M back to top-----MAKEUP:Relining ladles or furnace with refractories.MARTENSITE:Room temperature structure of steel formed as a result of a rapid quench from the austenitic condition. Hard, strong, and brittle structure.MECHANICAL PROPERTIES:Those properties of a material that reveal the elastic and inelastic reaction when force is applied or that improve the relationship between stress and strain.MELT DOWN:The process in which steel is transferred from the solid state into the liquid state by introducing electrical power to the scrap in the electric furnace.MICROSTRUCTURE:Microscopic structure of steel. Under a microscope, certain elements of the solidified metal are visible (crystal structure).MODULUS OF ELASTICITY:A measurement of the stress-per-unit strain, an indication of the resistance of the steel to deformation within its elastic limit.MOLD:An iron-casting container used to hold and cool molten metal as it solidifies.MOLD CLUSTER:A series of 6 or 8 molds positioned in a circular arrangement interconnected by runners.MOLD STOOL:Metal plate used to support each mold on the stool plate.-----O back to top-----ORE:A mineral from which the metal can be extracted.OXIDATION:Process in which carbon combines with oxygen to form oxides.-----P back to top-----PLAIN CARBON STEEL:Iron-carbon alloys with minimal alloy content.PLASTIC DEFORMATION:Permanent distortion of a material under the action of applied stresses.POWDER INJECTION:The injection of certain materials into the molten bath at the ladle refining station. The material is usually injected through a consumable lance using argon as a carrier gas.PULPIT:An enclosed operator's platform.-----Q back to top-----QUENCHING:The process of rapidly cooling the steel from a temperature above the critical temperature.QUENCH CRACKS:Cracks formed in a steel part during or after quenching that result from high-stress in cooling.-----R back to top-----REDUCTION:Process in which oxygen in removed from a compound.REFRACTORY:A substance which is infusible at the highest temperature it may be required to withstand in service; heat-resistant material.ROCKWELL HARDNESS:An indentation hardness test that measures hardness by determining, under load, the depth of penetration of an indenter, such as a steel ball. The hardness number is related to the depth of indentation; the greater the number, the harder the material.RUNNER:A channel through which molten metal or slag is passed from one receptacle to another.ROTARY/TEEMING NOZZLE:Mounted on the bottom of the ladle and used to regulate the flow of molten metal from the ladle into the trumpet. -----S back to top-----SCALE:An oxide of iron which forms on the surface of hot steel exposed to air or oxygen.SCARF:To remove surface defects from ingots, blooms, or billets, usually with a gas torch.SCRAP:Iron or steel discard, cuttings, or raw material which will be reprocessed.SEAM:Surface crack on a rolled product which has been closed but not by welding.SHEAR:A machine for cutting steel products.SIDE BOARDS:Sometimes referred to as hot top. Used to insulate top of mold to avoid large cavity in the top of the ingot as it cools.SKULL:A solid piece of steel left in a refractory-lined vessel after use that must be removed in order for the vessel to be reused; mainly used in reference to the ladle.SLAG:A crust formed on top of molten steel which primarily acts as an insulator. A medium through which chemical reactions occur across the boundary between the slag and the molten metal.SOAKING PIT:A furnace or pit for the heating of ingots to make their temperature uniform throughout in preparation for the rolling operation.SPALLING:Breaking away of refractory.SPIDER:A refractory brick that distributes the flow of molten metal from the trumpet toward the separate molds.STAND OF ROLLS:The simplest unit of a rolling mill, consisting of a set of rolls, the housings, bearings and guides required for the rolling of steel.STAINLESS STEEL:High-alloy steel, designed for resistance to corrosion and/or oxidation, containing high percentages of chromium (>4%). Some grades may also contain quantities of nickel.STEEL:Iron-based alloy containing carbon and other elements.STICKER:An ingot that has not separated from the mold.STOOL PLATE:Large metal plate that supports a circular cluster of ingot molds used in the bottom pouring operation. Steel flows down through a central fill tube (trumpet), through grooves (runners) in the bottom of the plate, and up into the ingots through holes in the bottom of the ingots.STRENGTH:Ability to resist applied forces.STRESS:The load per unit of area.SURFACE INSPECTION:The inspection of the surface of products for defects such as ingot cracks, scabs, seams, burned steel, laps, twist, guide marks, etc.-----T back to top-----TAPPING:The act of draining the molten metal from furnace to ladle.TEEMING:Pouring metal into ingot molds.TEMPERING:A process of reheating quench-hardened or normalized steel to a temperature below the transformation range, then cooling at any rate desired. Relieves internal stresses and imparts toughness and ductility.TENSILE STRENGTH:A measurement of the maximum load per unit of original area that a steel has prior to fracture.TOOL STEEL:Steel with high tempering temperatures with 1/2% to 1-1/2% carbon, significant (75%) alloy content and usually containing carbide stabilizers such as chromium, manganese, molybdenum, vanadium and tungsten.TOUGHNESS:Ability to absorb impact energy.TRUMPET:A funnel which serves to deliver molten metal to a junction of 6 or 8 runners.-----U back to top-----ULTRASOUND:High-frequency sound waves used to detect product defects.-----V back to top-----VACUUM ARC DEGASSING (VAD):(See ladle refining system.)-----Y back to top-----YIELD STRENGTH:A measurement of the amount of stress that gives the initial significant plastic, or permanent, deformation of the steel.。

图 3 试样 1 和 2 在不同温度时的力 学性能
3期
张 金柱等 铈及其碳化物对钢力学性能的影响
277
图 4 试样 1( a) 和试样 2( b) 在 873 K 的拉伸断口扫描像
图 4( b) ) 。显然, 固溶的铈原子和析出的铈碳化物 是拉伸断口的脆性断面率降低的 主要原因, 也是 试样 2 的 断面收缩率提高, 即塑性改善 的主要原 因。 3结 论
2 结果与讨论 通过金相详细观察, 并结合电子探针定量分析
和X 射线衍射分析, 确认试样中的铈碳化物为 CeC2[ 8, 9] 。除试样 4 只有微量稀土碳化物生成外, 其
他加铈的试样中均有大量的稀土碳化物相分布于 基体中。CeC2 在铸态试样中沿着晶界分布, 经压力 加工后沿加工方向排列[ 9] ; 铈含量较低的试样 2 和 试样 5 与试样 6 相比, 铈碳化物 量也相应 有所降 低。
1实 验 试样用工业纯铁块、石墨电极块, 在氧化镁坩
埚内, 由中频感应炉熔炼。钢 样熔清后, 加入金属 锰和硅, 温度约 1800 K 时再加入金属铈, 约 5 min 后, 浇成 5 kg 锭, 切去头部后, 锻成 15 mm # 15 mm 和 15 mm 的线材。冲击试样按 GB/ T 229 标准加 工, 1083 K, 15 min, 水淬, 773 K 回火。分别在室温 ( 295 K) 和 243 K, 用能量为 49 J 的冲击试验机测定 冲击吸收功( A KV) 。低应变静拉伸试验按 GB228 和 GB6397 标准, 材料经 1073 K, 20 min 炉冷处理。常 温拉伸试样在 1078 K, 保温 40 min, 在氩气中淬火。
试样 3 试样 4 试样 5 试样 6
1323 2
6