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Does the thermal spike affect low-energy ion-induced interfacial mixing

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arXiv:cond-mat/0302262v3 [cond-mat.mtrl-sci] 9 Oct 2003Doesthethermal-spikeaffectlow-energyion-inducedinterfacialmixing?

P.S¨ule,M.Menyh´ard,K.Nordlund

ResearchInstituteforTechnicalPhysicsandMaterialScience,

KonkolyThegeu.29-33,Budapest,Hungary,sule@mfa.kfki.huAcceleratorLab.,Helsinki,Finland(February2,2008)

Moleculardynamicssimulationshavebeenusedtoobtainthethree-dimensionaldistributionofinterfacialmixingandcascadedefectsinTi/Ptmultilayersystemduetosingle1keVAr+impactatgrazingangleofincidence.TheTi/Ptsystemwaschosenbecauseofitsrelativelyhighheat

ofmixinginthebinaryalloyandthereforeasuitablecandidatefortestingtheeffectofheatofmixingonion-beammixing.However,thecalculatedmixingprofileisnotsensitivetotheheatofmixing.Thereforethethermalspikemodelofmixingisnotfullysupportedundertheseirradiationconditions.Insteadwefoundthatthemajorityofmixingoccursafterthethermalspikeduringthe

relaxationprocess.Theseconclusionsaresupportedbyliquid,vacancyaswellasadatomanalysis.Theinterfacialmixingisinvariousaspectsanomalousinthissystem:thetimeevolutionofmixingisleadingtoaphasedelayforTimixing,andPtexhibitsanunexpecteddoublepeakedmixing

evolution.Thereasonstotheseeffectsarediscussed.PACSnumbers:61.82.Bg,79.20.Rf,81.40.Wx

I.INTRODUCTION

Withtheappearanceofnanotechnologytheimpor-

tanceofthinfilmsincreasedconsiderably.Eitherduring

makingthinfilmsbyanykindofvarioussputteringpro-

cessesorinthinfilmanalysis(variouskindsofsputter

depthprofilingtechniques)thethinfilmsystemissub-

jectedtolowenergyionbombardment.Forthisreason

thestudyoftheeffectsofthelowenergyionirradiation

ofthinfilmstructuresisofhighimportance.

Oneoftheeffectsofionbombardmentisinterfacialion

beammixing.Thistermisusedforthatprocesswhen

anoriginallysharpinterface(IF)betweenpureAand

Bmaterialsgetsbroaderduetoionbombardment.The

ionmixing(IM)phenomenonisknownforalongtime

[1].Themajorityofourknowledgereferstocaseswhen

theinterfacetobemixedisrelativelydeepinthematrix

(thatis,farfromthefreesurface)andconsequentlythe

ionenergyappliedisintherangeof100keV[2].

Severaltheoreticalapproachesandtechniqueshave

alsobeendevelopedandarathercoherentpictureseems

tohaveemerged[1,2].Thoughthereisnoprincipaldiffer-

encebetweenthelowandhighenergyionmixingstillthe

previousexperimentalandtheoreticaltechniquescannot

bedirectlyappliedforthelowenergycase.Themostim-

portantdifferencebetweenthehighandlowenergyion

mixingisthat(i)thelatteroccursclosetothefreesur-

faceand(ii)itsextentisobviouslymuchlessthanthat

ofhighenergymixing.

WiththeincreasingcomputationspeedMDsimula-

tionshavebecomeastandardtooltostudythelowen-

ergyionbeamsurfaceinteraction,andinterfacemixing

aswell.MDsimulationofIMhasbeenthesubjectof

severalstudiesinthelastdecades[1].IMinmultilayer

systemhasalsobeeninvestigatedbyseveralgroupsusing

MD[1,4,6,7].Acommonfeatureofthesestudiesisthat

onlyasingleionimpacthasbeenconsideredduringthesimulations.Experimentalanalysisofinterfacialmixing

inmultilayermetals,however,alwaysdealwithaseriesof

ionimpacts.Forinstance,Augerdepthprofilinganalysis

ofmultilayersshouldleadtotheremovalofthetarget

duringanalysis[9].Asafirststep,weinthisstudyfocus

onunderstandingthesingle-ionprocess.Togobeyond

thislevelwewillemployaseriesofionimpactsinthe

nextstudy.

Theothercommonfeatureofthestudiesavailableis

thattheyuseanormalangleofincidence.Weshould

liketomodelionmillinganddestructivedepthprofiling

techniques[9].Basedonexperimentalevidencesweknow

thatfortheoptimumapplicationofthesemethodsone

shouldapplylowenergyionbombardmentwithgrazing

angleofincidence(tominimizethesurfacemorphology

development).Thisarrangement,however,isfarfrom

thepreviousone.First,theangleofincidenceisgrazing

incontrasttonormalangleofincidence.Second,Pinzon

etal.[8]recentlyshowedbyMDcalculationthatthe

damagestructurechangeswithangleofincidence.At

grazingangleofincidenceionbombardmentthedefects

areconfinedclosetothesurface.

Anotherinterestingaspectofion-beammixingisthe-

oretical.Itisstillunclearwhetherthemechanismof

IMispurelyballisticorheatspikesplayessentialrole

inthemagnitudeofinterfacialmixing[1,2].Inparticu-

larwithinthethermalspike(TS)model[2]theheatof

mixing(∆Hm)isfoundtobeakeyquantityindetermin-

ingthemagnitudeofmixing.Theroleofheatofmixing

ongoverningmixingprocessesisquestionedbyR.Kelly

etal.[10].Theyemphasizedtheroleofresidualdefects

inmixing(longrangedeffects).Althoughthethermal

spikeconceptiswidelyaccepted,itsapplicabilityforlow-

energybombardmentsisnotstraightforward.MDsimu-

lationofcascadeshavebeenreportedwithevidencethat

localmeltingoccursduringthetermalspikephaseswhich

persistsforseveralpsinthe3−5keVenergyregime[11].

合集下载

镍基单晶高温合金杂晶缺陷的研究进展

镍基单晶高温合金杂晶缺陷的研究进展

第16卷 第1期 精 密 成 形 工 程 2024年1月 JOURNAL OF NETSHAPE FORMING ENGINEERING 129

收稿日期：2023-08-19

Received：2023-08-19

基金项目：国家自然科学基金（5210011310）；陕西省自然科学基础研究计划（2021JM-403）；陕西省教育厅科研计划（21JC027）；

西安市科技计划（2020KJRC0100）

Fund：National Natural Science Foundation of China(521001130); Natural Science Basic Research Program of Shaanxi Province

（2021JM-403）；Scientific Research Program of Shaanxi Provincial Education Department (21JC027)；Xi'an Science and Technology Plan(2020KJRC0100) 引文格式：陈楚玥, 霍苗, 简航岳. 镍基单晶高温合金杂晶缺陷的研究进展[J]. 精密成形工程, 2024, 16(1): 129-139. CHEN Chuyue, HUO Miao, JIAN Hangyue. Research Progress on Stray Grain Defects in Ni-based Single Crystal Superalloy[J]. Journal of Netshape Forming Engineering, 2024, 16(1): 129-139. *通信作者（Corresponding author） 镍基单晶高温合金杂晶缺陷的研究进展

陈楚玥，霍苗*，简航岳

（西安石油大学 材料科学与工程学院，西安 710065）

摘要：随着单晶涡轮叶片结构的不断优化和高温合金中难熔元素添加量的增大，镍基高温合金单晶叶片在

方钴矿的界面调控与热电性能

方钴矿的界面调控与热电性能

哈尔滨工业大学工学硕士学位论文

- I - 摘 要

方钴矿热电材料是综合性能较好的中温热电材料，由于具有较大的载流子

迁移率和Seebeck系数，使其具备高ZT值的潜力，但由于晶格热导率较高，

导致ZT值较低，本文主要通过高能球磨纳米化、引入石墨烯、液相压实构建

小角晶界等界面调控方式，降低晶格热导率，从而提高热电性能。采用XRD、

SEM、TEM、激光热导仪、电导率/塞贝克系数测试系统等方法研究了不同界

面调控方式对方钴矿组织结构和热电性能的影响规律，得到如下研究成果：

针对退火La

0.8Ti

0.1Ga

0.1Fe

3CoSb

12方钴矿，采用高能球磨结合放电等离子体

烧结（SPS）制备纳米结构块体材料，与参比样品相比，退火球磨样品的电导

率基本一致，但塞贝克系数增大，相应功率因子也较高。退火球磨样品结构纳

米化增强了对声子的散射作用，降低了晶格热导率，623K时晶格热导率达到

最低为0.8Wm-1

K-1

，较参比样品降低了33%。通过高能球磨实现结构的纳米化

不仅改善了电性能，也有效地降低晶格热导率，进而提高了热电性能，退火球

磨样品的热电优值在723K时从0.8提升到1.05。采用PECVD法在p型退火

La

0.8Ti

0.1Ga

0.1Fe

3CoSb

12方钴矿粉体表面原位组装石墨烯，制备出p型方钴矿/石

墨烯复合材料，发现石墨烯的引入对p型La

0.8Ti

0.1Ga

0.1Fe

3CoSb

12方钴矿的电导

率无明显影响，但塞贝克系数略有提高。石墨烯的引入明显降低p型

La

0.8Ti

0.1Ga

0.1Fe

3CoSb

12方钴矿的晶格热导率，673K时具有最低值为0.9Wm-1

K-

1

，较参比样品降低了25%。石墨烯的引入对电性能稍有改善的同时，明显降

低晶格热导率，使ZT值在723K时从0.8提高到1.00。

采用熔体旋甩结合液相压实法制备n型Ce

xCo

4Sb

14.4（x=0.1、0.125、0.15、

0.175、0.2）方钴矿，发现电导率随着填充量的增加而增大，Seebeck系数与电

强流脉冲离子束辐照钢靶热力学效应数值模拟

强流脉冲离子束辐照钢靶热力学效应数值模拟

２　０　Ｏ　８年１　０月　第２　７卷第５期　沈阳理工大学学报　

ＴＲＡＮＳＡＣＴＩＯＮＳ　０Ｆ　ＳＨＥＮＹＡＮＣ　ＬＩＧＯＮＧ　ＵＮＩＶＥＲＳＩＴＹ　Ｖ０１．２　７　Ｎｏ．５　０ｃＬ　２　０　Ｏ　８　

文章编号：ｌ００３一ｌ２５１（２０ｏ８）Ｏ５—００８０—０４　

强流脉冲离子束辐照钢靶热力学效应数值模拟　

万柄男　，张　罡　，莫春立　

（１．沈阳理工大学中俄联合高能束流实验室，辽宁沈阳ｌ１叭６８；２．沈阳航空工业学院）　

摘　要：为了揭示强流脉冲离子束辐照材料表面的热力学效应，介绍了强流脉冲离子柬　与钢靶相互作用的理论模型．以此为基础，通过数值模拟计算了离子能量为３００ｋｅＶ，束　

流密度为２００Ａ／ｃｍ　的离子柬与钢靶相互作用的热力学效应，得到了温度场分布、温度　梯度分布，以及应力与应力波传播过程的模拟计算结果，结果表明辐照后材料表面在极　短时间内发生了剧烈的温度与应力变化．　

关键词：强流脉冲离子束；热力学效应；数值模拟　中图分类号：ＴＧ１７４．４４４　文献标识码：Ａ　

ＮｕｍｅｒｉｃａＩ　ＳｉｍｕＩａｔｉＯｎ　Ｏｎ　Ｔｈｅｒｍａ１．ｍｅｃｈａｎｉｃａｌ　Ｅｆｆｅｃｔｓ　Ｏｆ　Ｓｔｅｅｌ　

Ｔａｒｇｅｔ　Ｉｒｒａｄｉａｔｅｄ　ｂｙ　Ｈｉｇｈ—ｉｎｔｅｎｓｉｔｙ　Ｐｕｌｓｅｄ　Ｉｏｎ　Ｂｅａｍ　

ＷＡＮ　Ｂｉｎｇ—ｎａｎ　，ＺＨＡＮＧ　Ｇａｎｇ　，ＭＯ　Ｃｈｕｎ—ｌｉ　

（１．Ｓｈｅｎｙａｎｇ　Ｌｉｇ０ｎｇ　Ｕｎｉｖｅｒｓｉｔｙ，Ｓｈｅ“ｙａｎｇ　ｌｌ０ｌ６８，Ｃｈｉｎａ；２．Ｓｈｅｎｙａｎｇ　Ｉｎｓｔｉｔｕｔｅ　０ｆＡｅｍｎａｔｉｃａ１　Ｅｎｇｉｎｅｅｒｉｎｇ）　

Ａｂｓｔｒａｃｔ：Ｉｎ　０ｒｄｅｒ　ｔｏ　ｓｔｕｄｙ　ｔｈｅ　ｔｈｅ丌Ｉｌａｌ—ｍｅｃｈａｎｉｃａｌ　ｅｆｌｆｅｃｔ　０ｎ　ｍｅｔａｌ　ｓｕＩｆａｃｅ　ｉＩＴａｄｉａｔｅｄ　ｂｙ　ｈｉｇｈ　

ｉｎｔｅｎｓｉｔｙ　ｐｕｌｓｅｄ　ｉｏｎ　ｂｅａｍｓ（ＨＩＰＩＢ），ａ　ｍ０ｄｅｌ　ｆ０ｒ　ｔｈｅ　ｉｎｔｅｍｃｔｉ０ｎ　０ｆ　ｈｉｇｈ　ｉｎｔｅｎｓｉｔｙ　ｐｕｌｓｅｄ　ｉ０ｎ　ｂｅａｍｓ　ｗｉｔｈ　ｓｔｅｅｌ　ｔａｒｇｅｔ　ｉｓ　ｄｅｓｃｒｉｂｅｄ．Ｔｈｅｎ　ｔｈｅ　ｔｈｅｒｍａｌ—ｍｅｃｈａｎｉｅａｌ　ｅｆｌｆｅｃｔｓ　ｏｎ　ｔｈｅ　ｓｔｅｅＩ　ｔａ唱ｅｔ　

耐盐型太阳能驱动界面光热材料及蒸发器的研究进展

耐盐型太阳能驱动界面光热材料及蒸发器的研究进展

化工进展Chemical Industry and Engineering Progress2023 年第 42 卷第 7 期

耐盐型太阳能驱动界面光热材料及蒸发器的研究进展

李吉焱，景艳菊，邢郭宇，刘美辰，龙永，朱照琪（兰州理工大学石油化工学院，甘肃 兰州 730050）摘要：太阳能驱动界面蒸发技术（SDIE）依靠光热材料和蒸发器进行海水淡化，因光热转换效率高、环境友好、制造工艺简单和材料丰富等优点引起了学者们的广泛关注。但在海水淡化过程中，光热材料和蒸发器表面盐结晶的积累会直接影响太阳能界面蒸发效率，解决光热材料和蒸发器表面盐结晶问题是SDIE中重要的一步。本文简述了近年来耐盐型光热材料及蒸发器的设计理念与研究现状，阐述了不同耐盐设计的优点和局限性，梳理了其耐盐机制和性能，分析表明通过调控光热材料的孔结构、亲-疏水性、离子基团等方法可以增强光热材料的耐盐性，通过调控盐溶液的浓度和盐的结晶位置等可设计多种耐盐型蒸发器，讨论了目前在SDIE中解决盐结晶问题存在的共性问题并提出未来的研究挑战，以推进未来SDIE的研究与发展。关键词：太阳能；界面蒸发；海水淡化；光热材料；耐盐中图分类号：TQ09 文献标志码：A 文章编号：1000-6613（2023）07-3611-12Research progress and challenges of salt-resistant solar-driven interface photo-thermal materials and evaporatorLI Jiyan，JING Yanju，XING Guoyu，LIU Meichen，LONG Yong，ZHU Zhaoqi(School of Petrochemical Technology, Lanzhou University of Technology, Lanzhou 730050, Gansu, China)Abstract: Solar-driven interfacial evaporation (SDIE), which relies on photothermal materials and evaporators for desalination, has attracted widespread attention from scholars because of its high photothermal conversion efficiency, environmental friendliness, simple manufacturing process and abundant materials. Addressing the salt crystal buildup on the surface of photothermal materials and evaporators is a crucial stage in SDIE because it will directly affect the evaporation efficiency throughout the desalination process. This paper briefly described the design concepts and research status of salt-tolerant photothermal materials and evaporators in recent years, illustrated the advantages and limitations of different salt-tolerant designs, and sorted out their salt-tolerance mechanisms and performance. The analysis demonstrated that the salt resistance of photothermal materials can be enhanced by regulating the pore structure, hydrophilic-hydrophobic and ionic groups of photothermal materials. A variety of salt-resistant evaporators can be designed by regulating the concentration of salt solution and the crystallization position of salt. In addition, common problems in solving salt crystallization problems in SDIE were discussed and future research challenges were proposed to advance the future research and development of SDIE.Keywords: solar energy; interfacial evaporation; desalination; photothermal materials; salt resistance􀤕􀤕􀤕􀤕􀤕􀤕􀦕􀤕􀦕􀤕􀤕􀤕􀤕􀤕􀤕􀦕􀤕􀦕综述与专论DOI：10.16085/j.issn.1000-6613.2022-1732