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有效抑制电气化铁路对油气管道管地电位影响的技术

杨理践 , 黄平 , 高松

材料保护

针对铺设在直流电气化铁路附近埋地油气管道管地电位过度负偏移的问题,研究了土壤直流杂散电流对管道的干扰机理以及管道防腐蚀涂层阴极剥离的形成原因,提出了一种管道与接地极(如扁钢、铜、锌带等)之间快速通断的方法,设计了抑制管地电位过度负偏移应用系统.现场测量结果表明,该系统可将管地电位钳制在预先设置的电位附近,有效抑制了管地电位过度负偏移现象,整机系统工作电流仅30 mA.

关键词: 管地电位 , 负偏移 , 直流杂散电流 , 阴极剥离 , 接地极

管道沟槽状腐蚀缺陷的有限元仿真分析

杨理践 , 严妍 , 高松

腐蚀与防护

采用ANSYS有限元仿真对管道的局部腐蚀进行了仿真分析,以沟槽状缺陷为研究对象,采用建立几何模型、进行网格划分、加载载荷和约束,以及后处理等方法,模拟管道在实际工作环境中的运行状况;计算出沟槽状缺陷区域在给定管道运行压力下所产生的应力和管道形变位移的大小。结果表明,管道腐蚀缺陷处的应力和形变位移量可以作为长输管道缺陷评价的参考依据。

关键词: 局部腐蚀 , 沟槽状缺陷 , 有限元仿真 , 管道评价 , 应力 , 形变位移

应用齐波夫定律预测高松山金矿床资源量

尹西军 , 庞文龙 , 刘浩 , 张剑盈 , 黄芳根

黄金

黑龙江高松山金矿床经过20多年的找矿工作,资源量已具有大型规模,但由于目前认识上有分歧,对矿区前景有不同的看法.齐波夫定律在地质矿产资源预测上有一定的应用效果,利用齐波夫定律对高松山金矿床资源量进行预测,得出高松山金矿床仍具有很大的潜力,其预测远景资源量为88 t.

关键词: 齐波夫定律 , 预测量 , 资源量 , 高松山金矿床

黑龙江高松山金矿床地质特征及找矿前景分析

陈桂虎 , 王艳忠 , 庞文龙 , 佟智强 , 薛继广 , 赵洪海 , 尹西君

黄金

高松山金矿床是近几年在小兴安岭—张广才岭成矿带北段发现的大型浅成低温热液矿床,已探获资源量22 t,具有优越的成矿地质条件和良好的找矿前景,已被列为国家首批整装勘查区.为了揭示其成矿规律和找矿潜力,且为今后的整装勘查与资源潜力评价提供有意的参考,在分析高松山金矿床成矿地质背景和矿床地质特征基础上,研究其成矿特点,发现矿脉产出受菱形构造控制,呈等距分布,在垂向上具有向西侧伏,分段富集特征;结合成矿规律和物化探异常特征,指出矿区存在多条平行矿脉,NWW 向矿体深部成矿潜力大;提出沙阿其河断裂是导矿构造,可能也是容矿构造,在下一步的勘查工作应加以重视.

关键词: 成矿规律 , 地质特征 , 找矿前景 , 整装勘查 , 高松山金矿床

黑龙江省逊克县高松山金矿区岩石地球化学特征

尹西君 , 连永牢 , 潘超

黄金 doi:10.3969/j.issn.1001-1277.2010.10.005

通过对高松山金矿床特征、地球化学特征的分析研究,认为高松山金矿床为浅成低温热液型金矿床,成矿地层是甘河期火山岩,以亚碱性系列之钙碱性高钾火山岩为特征.火山岩稀土元素分析结果表明,该火山岩属轻稀土富集型,铕无明显异常,稀土配分曲线为平缓的右倾.岩石微量元素曲线形态基本相似,表明岩浆具有同源特点.火山岩成因类型为壳-壳幔活动大陆边缘的产物.岩浆演化以分异作用为主,并受一定陆壳混染.

关键词: 地球化学特征 , 稀土元素 , 微量元素 , 矿床成因 , 黑龙江

黑龙江省逊克县高松山金矿床开采技术条件分析

连永牢 , 赵洪海 , 薛继广 , 白东照 , 杨帅 , 邵长来

黄金 doi:10.11792/hj20130605

通过对高松山金矿区地下水类型及补给、径流、排泄条件、充水因素等进行研究,确定了矿床的水文地质条件;根据不同围岩岩性的稳固性评价及矿区的地质地貌情况,对矿区的工程地质和环境地质条件进行了分析,基本阐明了矿床开采技术条件,为矿山的建设和开采提供了参考依据。

关键词: 开采技术条件 , 水文地质 , 工程地质 , 环境地质 , 高松山金矿床 , 黑龙江

第四届“吴仲华奖励基金”评选出获奖者

工程热物理学报

根据《吴仲华奖励基金章程》(吴奖[2008]01号),经各高等院校、中国工程热物理学会和中国科学院工程热物理研究所认真评选和推荐,吴仲华奖励基金理事会评审并确定授予青年学者戴、罗坤、唐桂华“吴仲华优秀青年学者奖”,授予程雪涛等10位同学“吴仲华优秀学生奖”。

关键词: 基金 , 奖励 , 评选 , 获奖者 , 中国科学院 , 青年学者 , 物理研究所 , 高等院校

INVESTIGATION OF HYDROGEN INDUCED DUCTILE BRITTLE TRANSITION IN 7175 ALUMINUM ALLOY

金属学报(英文版)

桑危郑牛樱裕桑牵粒裕桑希。希啤。龋伲模遥希牵牛。桑危模眨茫牛摹。模眨茫裕桑蹋拧。拢遥桑裕裕蹋拧。裕遥粒危樱桑裕桑希。桑。罚保罚怠。粒蹋眨停桑危眨汀。粒蹋蹋希?##2##3##4##5INVESTIGATIONOFHYDROGENINDUCEDDUCTILEBRITTLETRANSITIONIN7175ALUMINUMALLOY$R.G.Seng:B.JZhong,MG.ZengandP.Geng(DepartmentofMaterialsScierce,ScienceCollege,NorthearsternUniveisity,Shenyang110006,ChinaMaruscriptreceived4September1995inrevisedform20April1996)Abstrac:Effectsofhydrogenonthemechanicalpropertiesofdifferentlyaged7175aluminumalloyswereinvestigatedbyusingcathodicH-permeation,slowstrainratetensionandsoon.Theresultsindicatethatboththeyieldstressandthepercentagereductionofareadecreasewithincreasinghydrogenchargingtime,andthedegreeofreductiondecreasesasagingtimeincreasesforthesamehydrogenchargingtime.Keywords:hydrogeninducedductile-brittletransition,7175aluminumalloy,mechanicalproperty,cathodicH-permeation1.IntroductionForalongtimehydrogenembrittlementproblemwasthoughttobeabsentinhighstrengthaluminiumalloybecausethesolutiondegreeofhydrogeninaluminumatcommontemperatureandpressureisverysmall.However,hydrogenembrittlementphenomenonwasfoundinaluminumalloyduringtheinvestigationofstresscorrosionandcorrosionfatigue[1-5].Therehavebeenonlyafewreportsofhydrogeninducedsofteningandhardening.Inthispaper,theeffectsofhydrogenonmechanicalpropertiesof7175aluminumalloywereinvestigatedbyusingcathodicalchargingwithhydrogenandslowtensiontests.2.ExperimentalProcedureTheexperimentalmaterialwas7175aluminumalloyforgingintheformofa43mminthicknessandwithcomposition(wt%).5.41Zn,2.54Mg.1.49Cu,0.22Cr,0.1Mn.0.1Ti,0.16Fe.0.11Si,balancedbyA1.Alloyplateof1.5mminthicknesswasobtainedbyhot(465℃)andtoldrollingto83%reductioninthickness.Thelongaxisofhydrogenchargedspecimensisalongtherollingdirection.Allspecimensweresolidsolutionedat480℃for70min,followedtyimmediatequenchinginwaterandthenagedat140℃for6h(A),16h(B)and98h(C).Thetreatmentof6hiscorrespondingtotheunderagedstate.16hthefirstpeak-agedstateand98hthesecondpeak-agedstate.Thespecimenswerepolishedsuccessivelyusingemerypaperbeforehydrogencharging.Thetensilespecimenswerecathodicallychargedina2NH_2SO_4solutionwithasmallamountofAs_2O_3forpromotinghydrogenabsorption,andwithacurrentdensityof20±1mA/cm ̄2atroomtemperature.ThehydrogencontentanalysiswascarriedoutonanLT-1Amodelionmassmicroprobeafterthesputteringdepthreached8nm.Theioncurrentsofhydrogenandaluminuminvariousagedstateswererecordedunderthesamecondition.ThetensiletestswereperformedonanAG-10TAmodeltestmachinewhichwascontrolledbycomputer.3.ExperimentalResultsTheratioofioncurrentstrengthofhydrogentoaluminumisrelatedtohydrogenconcentrationinhydrogenchargedspecimen.TheresultswereshowninTable1Thehydrogencontentincreaseswiththeincreaseincharingtime.Ofthethreeagedstates,theunderagedspecimenhasthehighesthydrogencontent.Theratioofyieldstrengthofhydrogenchargedandunchargedspecimenschangeswithhydrogenchargingtime,asshowninFig.1Itcanbeseenthattheyieldstrengthofhydrogenchargedspecimendecreasewithincreasinghydrogenchargingtime.Atthesamechargingtime,theyieldstressdecreasestheleastinthesecondpeak-agedstate,anddecreasesthemostintheunderagedstate.Itindicatesthattheunderagedspecimenismostsensitivetohydrogeninducedsoftening,whichisconsistentwiththeresultsofanotherhighstrengthaluminumalloy[6].TherelativechangesoftheradioofreductionofareawithhydrogenchargingtimearesummarizedinFig.2,whereΨ ̄0andΨ ̄Harethepercentagereductionofareaofthesamplewithoutandwithhydrogenchargingrespectively.Theradioofreductionofareareduceswhenhydrogenchargingtimeincreases,andthedecreasingdegreeofreductionofareaincreaseswithincreasingagingtime,ie,,theunderagedstateisthemostsensitivetohydrogenembrittlement.4.DiscussionItisknownfromtheresultsabovethatcathodicalchargingwithhydrogenleadstotheobviousdecreaseinthetensilestrengthandplasticityThisisbecausealargeamountofsolidsolutionhydrogenentersthespecimenintheprocessofhydrogenchargingSolidsolutionhydrogenisliabletoenterthecentreofdislocationundertheactionofdislocationtrap,henceraisingthemovabilityofdislocation.Thereforethedislocationsinhydrogenchargedspecimenmoveeasierthaninunchargedspecimen.soresultinginthereductionofyieldstrength[7].Whendislocationstartstomove,thecrystallatticeresistance(P-Nforce)whichitmustovercomeisgivenby:whereμismodulusofshear,visPoissonratio,aisspanofslipplane,bisatomspanofslipdirection.Moreover.theotherresistanceofdislocationmotionmayarisefromtheelasticinteractionofdislocation,theactionwithtreedislocationandetc.,itcanbeexpressedasfollows:whereαisconstant,XisdislocationspanSotheresistanceofdislocationmotioncanbewrittenasfollows:Becausehydrogenatomsreducetheatombondingstrengthafterhydrogencharging,shearmodulusμdecreasesandresultsinthereductionoff,therebytheyieldstressdecreases.Asthecentreofdislocationistheseriousdistortionzoneoflattice.thestresscanberelaxedafterhydrogenatomstuffing,andthesystemenergydecreases.Thusthecentreofdislocationisastrongtrapofhydrogen[8].Therefore,amovabledislocationcaptureshydrogenandmigratestograinboundaries.phaseboundariesorsurfaceofthespecimen,promotingthecrackiesformationandgrowth,thuscausingthelossofplasticity.Sincethelocalenrichmentofhydrogenisrealizedbydislocationtransporting(inthestageofdeformation),thelargerthereductionofyieldstress.theearlierarehydrogenatomstransportedtotheplaceofenrichment.Inaddition,thedamageofatombondingstrengthinducedbyhydrogenmakesthefracturestressdecrease[9]:whereCHishydrogenconcentration.σ_thisfracturestrengthbeforehydrogenchargingandisfracturestrengthafterhydrogencharging.Eq.(4)showsthatthematerialsmaybefracturedatalowerstraini.e.,brittlefractureoccurs.5.Conclusions(1)Hydrogencontentofdifferentlyagedspecimensincreaseswithincreasinghydrogenchargingtimethecapabilityofthealloytoabsorbhydrogeninunderagedstateisthestrongest.(2)Theyieldstressaswellasthepercentagereductionofareaof7175aluminumalloydecreaseashydrogenchargingtimeincreasesundervariousagedstates.(3)Underagedstateismostsensitivetohydrogeninducedsofteningandhardening.(4)Anexplanationwasofferedforthephenomenonofhydrogeninducedsofteninginthestageofdeformation,andhardeninginthestageoffracture.REFERENCES||1G.KKock,Corrosion35(1979)73.2M.K.TsengandH.LMarcus,Scr.Metall.15(1981)427.3PSFao.M.GaoandR.P.Wei,Scr.Metall.19(1985)265.4R.G.SongandM.K.TsengJ.NortheasternUniversity15(1994)5(inChinese).5R.K.Viswanadham,T.S.sunandJ.A.S.Green,Metall.Trans.11A(1980)85.6J.Liu,M.KTsengandB.R.Liu.NonferrousMiningandMetallrgy5(1989)33(inChinese).7LChen,WXChen,ZHLiuandZ.Q.Hu,InFrocofthe1stNationalConfonAl-LiAlloys(Sheryang.China,1991)p.328(inChinese).8Z.HLiuL.ChenW.XChenY.X.ShaoandZ.Q.Hu,InProc.ofthe1stNationalConfonAl-LiAlloys(Shenyang,China,1991)p.334(inChinese).9R.A.OrianiandF.H.Josephic,ActaMetall.22(1974)1065.##61G.KKock,Corrosion35(1979)73.2M.K.TsengandH.LMarcus,Scr.Metall.15(1981)427.3PSFao.M.GaoandR.P.Wei,Scr.Metall.19(1985)265.4R.G.SongandM.K.TsengJ.NortheasternUniversity15(1994)5(inChinese).5R.K.Viswanadham,T.S.sunandJ.A.S.Green,Metall.Trans.11A(1980)85.6J.Liu,M.KTsengandB.R.Liu.NonferrousMiningandMetallrgy5(1989)33(inChinese).7LChen,WXChen,ZHLiuandZ.Q.Hu,InFrocofthe1stNationalConfonAl-LiAlloys(Sheryang.China,1991)p.328(inChinese).8Z.HLiuL.ChenW.XChenY.X.ShaoandZ.Q.Hu,InProc.ofthe1stNationalConfonAl-LiAlloys(Shenyang,China,1991)p.334(inChinese).9R.A.OrianiandF.H.Josephic,ActaMetall.22(1974)1065.##A##BINVESTIGATION OF HYDROGEN INDUCED DUCTILE BRITTLE TRANSITION IN 7175 ALUMINUM ALLOY$$$$R.G.Seng: B.J Zhong, MG. Zeng and P. Geng(Department of Materials Scierce, Science College,Northearstern Univeisity, Shenyang 110006, China Maruscript received 4 September 1995 in revised form 20 April 1996)Abstrac:Effects of hydrogen on the mechanical properties of differently aged 7175 aluminum alloys were investigated by using cathodic H-permeation, slow strain rate tension and so on. The results indicate that both the yield stress and the percentage reduction of area decrease with increasing hydrogen charging time, and the degree of reduction decreases as aging time increases for the same hydrogen charging time.

关键词: :hydrogen induced ductile-brittle transition , null , null , null

ATOMIC FORCE MICROSCOPY OBSERVATION OF MAGNETRON SPUTTERED ALUMINUM-SILICON ALLOY FILMS

金属学报(英文版)

粒裕希停桑谩。疲希遥茫拧。停桑茫遥希樱茫希校佟。希拢樱牛遥郑粒裕桑希。希啤。停粒牵危牛裕遥希。樱校眨裕裕牛遥牛摹。粒蹋眨停桑危眨停樱桑蹋桑茫希。粒蹋蹋希佟。疲桑蹋停?##2##3##4##5ATOMICFORCEMICROSCOPYOBSERVATIONOFMAGNETRONSPUTTEREDALUMINUM-SILICONALLOYFILMSJ.W.Wu,J.H.FangandZ.H.Lu(NationalLaboratoryofMoleculeandBiomoleculeElectronics,SoutheastUniversity,Nanjing210096,ChinaManuscriptreceived27October1995)Abstrcat:Twodifferentsurfacemorphologycharacteristicsofmagnetronsputteredaluminumsilicon(Al-Si)alloyfilmsdepositedat0and200℃wereobservedbyatomicforcemicroscopy(AFM).Oneisirregularlyshapedgrainsputtogtheronaplane.TheotherisirregularlyshapedgrainsPiledupinspace.Nanometer-sizedparticleswithheightsfrom1.6to2.9nmwerefirstobserved.Onthebasisoftheseobservationsthegrowthmechanismofmagnetronsputteredfilmsisdiscussed.Keywords:magnetronsputtering,Al-Sialloy,surfacemorphology,atomicforcemicroscopy,filmgrowthmechanism1.IntroductionTheuseofaluminumalloys[1,2],inparticularAl-Si,isacommonfeatureinmanysinglelevelandmultilevelinterconnectionschemesadoptedinthemanufactureofmicroelectronicdevicesbecauseofseveraldesirableproperties.TheAl-Sigrainmorphology(size.geometryanddistributionofgrainsisassociatedwithstepcoverage[3],electromigration[4]andinterconnectsresistivity[5]etc..Thus,characterizationofAl-Sialloysurfacemorphologyisveryimportant,especiallywhenintegratedintensityincreasesandlinewidthsof0.3to0.5μmbecomecommon.Inthepasttwentyyears,theAl-Sialloysurfacemorphologywhichaffectsthereliabilityofmicroelectronicdeviceshasbeenwidelyinvestigatedbyscanningelectronmicroscopy(SEM),transmissionelectronmicroscopy(TEM)etc.[5-7].However,SEMandTEMhavetheirlimitationorinconvenience,forexample,theverticalresolutionofSEMisnothighandTEMneedscomplexsamplepreparation.Recently,anewgrainboundaryetchingmethodwasproposed ̄[8]whichalsoneedstroublesomechemicaletching.Atomicforcemicroscopy(AFM),sinceitsemerging,hasbecomemoreandmoreusefulinphysics,chemistry,materialsscienceandsurfacescience,becauseofitshighresolution,easeofsamplepreparationandrealsurfacetopography.Recently,discussion[9,10]waspresentedonhowAFMwillplayaroleinsemiconductorindustry.Asaresponsetothisdiscussion,weusedAFMtoinvestigateAl-SialloysurfacemorphologyandhaveobtainedsomeresultswhichcannotberevealedbySEMorTEM.ThisindicatesthatAFMisagoodcharacterizationtoolinsemiconductorindustry.2.SamplePreparationInourexperiments,aluminumwith30ppmsiliconwassputteredonsiliconsubstrateinbatchdepositionmodeAllthreefilmswiththicknessof1.6μmweredepositedusinganargonsputteringpressureof4.2×10 ̄-3Pa.TheotherdepositionparametersaredescribedinTable1.Thesubstratewascleanedusingstandardpremetallizationcleaningtechniquespriortofilmdeposition.3.ExperimentalResultsandDiscussionTheAFMmeasurementswereperformedonacommercialsystem(NanoscopeIII,DigitalInstruments,SantaBarbara).Thetipismadeofmicrofabricatedsiliconnitride(Si_3N_4)Itisattachedtoa200μmcantileverwithaforceconstantofabout0.12N/m.Beforethesurfaceofsamplewasexamined.agoodtipwithananometer-sizedprotrusionatitsendwasselectedbeforehand,whichcanbeobtainedbyimagingtheatomicstructureofmicasubstrateandagoldgrid.AtypicaloperatingforcebetweenthetipandAl-Sisamplesurfaceisoftheorderof10 ̄-8Nandallimagesweretakenatroomtemperatureinair.AtypicaltopographicviewoftheAl-SifilmsisshowninFig.1(allimagescansizeis5by5μma,bandcarerespectivelyforsample1,2,and3).FromFig.la,itcanbeseenthatirregularlyshapedgrainstiltinginvaryingdegreespileupinspace,andgroovesamongtheirregularlyshapedgrainsaredifficulttodecideatacertainarea(wedefineitascharacteristicA).Toourknowledge,onreportsonthesurfacemorphologyhavebeenpresentedbefore.InFig1b,however,irregularlyshapedgrainsassembleonaPlaneandgroovesamongtheirregularlyshapedgrainsareeasytodecide(wedefineitascharacteristicB),whichisinagreementwithmanypreviousreports[5-7].InFig.1c,bothcharacteristicA(arrowA)andcharacteristicB(arrowB)wereobserved.IndoingAFMexperiments,weselectedfivedifferentscanareastobeimagedforeachsampleandfoundthatallimagesofeachsamplearerespectivelysimilartoFig.1a,bandc.Also,wenotedthatthesurfaceofinFig.1a.WethinkthatdepositionparameterswillinfluenceAl-Sisurfacemorphology,andthetiltedgrainsmaybesusceptibletomicrocracking.Byreducingthescansizeareato2by2μm(Fig.2aandb).Weobtainedmanyidenticalresultsasdescribedabove,suchasirregularlyshapedgrainsetc.Forthefirsttime,wefoundnanometersizedparticlesonirregularlyshapedgrainsurfacewhichcannotberevealedbySEMbecausethediameterofthesenanoparticlesisabout10nmandtheheightofthesenanoparticlesisintherangeof1.6to2.9nm.Inimaging,wenotedthatrotatingthescandirectionandchangingthescanfrequencydidnotaffectthestructureofthesegrainsasshowninFig.2aandb,rulingoutthepossibilitythatscanninginfluencedtheshapeoftheseparticlesorcausedsomesimilarimagingartifacts.Also,wenotedthatthenanoparticleswerenotobservedontheslopesofthegrooves(Fig.2aandb).Thisphenomenoncanbeexplainedasfollows:thepotentialenergyattheslopeislargerthanthatelsewhere,sotheparticlesseemmorelikelytobedepositedontheseareaswithlowerpotentialenergy.Fig.2c,scansize250by250nm,isazoomtopographicimage(whiteoutlineinb).Itshowsunevendistributionofthenanoparticles.Andtheheightdifferenceofthenanoparticlesindicatesdifferentgrowingspeed.Wethinkbasedonthemorphologyofnanoparticles,thattheheightdifferenceandunevendistributionofthesenanoparticlesshowdifferentgrowingadvantageandindicatethatatomshaveenoughenergytomovetoasuitablegrowingspot.Theenergymaybefromthefollowingsources:surfacetemperaturefluctuation,stressdifferenceorcollisionbetweenhighspeedsputteredatoms.Thesenanoparticlesgoongrowingandformmanyirregularlyshapedgrains.AndtheseirregularlyshapedgrainsfurtherconnecteachotheraccordingtocharacteristicAorB,finallyformingtheAl-Sisurfacemorphology.4.ConclusionWecandrawthefollowingconclusionsfromtheabove.First,theexperimentalresultsshowedthatAFMisapowerfultooltoinvestigatethedetailsofAl-Sisurfacemorphologywhichcangreatlyenrichourknowledgeofthefilmgrowthmechanism.Second,depositionconditionsplayanimportantroleindeterminingtheAl-Sisurfacemorphology.Third,thetwoAl-Sisurfacemorphologycharacteristicsarethatirregularlyshapedgrainsassembleonaplaneandirregularlyshapedgrainstiltinginvaryingdegreespileupinspace.Fourth,forthefirsttime,nanoparticleswereobservedonirregularlyshapedgrainsurfacewhichsuggestedthatthefilmgrowthmechanismwasbyinhomogeneousnucleation.Acknowledgements-BeneficialdiscussionswereheldwithDr.ZhenandMr.Zhu.ThisworkwaspartiallysupportedbytheNationalNaturalScienceFoundationofChina.RFFERENCES||1D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)127.2D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)131.3D.pramanikandA.N.Saxena,SolidStateTechnol.33(1990)73.4S.S.IyerandC.Y.Worg,J.Appl.phys.57(1985)4594.5J.F.Smith,SolidStateTechnol.27(1984)135.6D.GerthandD.Katzer,ThinSolidFilm208(1992)67.7R.J.WilsonandB.L.Weiss,ThinSolidFilm207(1991)291.8E.G.Solley,J.H.Linn,R.W.BelcherandM.G.Shlepr,SolidStateTechnol33(1990)409I.SmithandRHowland,SolidStateTechnol.33(1990)53.10L.Peters,SemiconductorInternational16(1993)62.##61D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)127.2D.pramanikandA.N.Saxena,SolidStateTechnol.26(1983)131.3D.pramanikandA.N.Saxena,SolidStateTechnol.33(1990)73.4S.S.IyerandC.Y.Worg,J.Appl.phys.57(1985)4594.5J.F.Smith,SolidStateTechnol.27(1984)135.6D.GerthandD.Katzer,ThinSolidFilm208(1992)67.7R.J.WilsonandB.L.Weiss,ThinSolidFilm207(1991)291.8E.G.Solley,J.H.Linn,R.W.BelcherandM.G.Shlepr,SolidStateTechnol33(1990)409I.SmithandRHowland,SolidStateTechnol.33(1990)53.10L.Peters,SemiconductorInternational16(1993)62.##A##BATOMIC FORCE MICROSCOPY OBSERVATION OF MAGNETRON SPUTTERED ALUMINUM-SILICON ALLOY FILMS$$$$J.W.Wu,J.H. Fang and Z.H.Lu (National Laboratory of Molecule and Biomolecule Electronics,Southeast University,Nanjing 210096, China Manuscript received 27 October 1995)Abstrcat:Two different surface morphology characteristics of magnetron sputtered aluminumsilicon(Al-Si)alloy films deposited at 0 and 200℃ were observed by atomic force microscopy(AFM).One is irregularly shaped grains put togther on a plane.The other is irregularly shaped grains Piled up in space. Nanometer-sized particles with heights from 1.6 to 2.9 nm were first observed. On the basis of these observations the growth mechanism of magnetron sputtered films is discussed.

关键词: :magnetron sputtering , null , null , null , null

CRYSTALLIZATION OF Fe_(38)Ni_(39)Si_(10)B_(13) METALLIC GLASS UNDER HELIUM ION IRRADIATION

金属学报(英文版)

茫遥伲樱裕粒蹋蹋桑冢粒裕桑希。希啤。疲錩(38)Ni_(39)Si_(10)B_(13) METALLIC GLASS UNDER HELIUM ION IRRADIATION##2##3##4##5CRYSTALLIZATIONOFFe_(38)Ni_(39)Si_(10)B_(13)METALLICGLASSUNDERHELIUMIONIRRADIATION$YANGQifa(ChinaInstituteofAtomicEnergy,Beijing)ZHANGGuoguang;SHENWanshui(UniversityofScienceandTechnologyBeijing)Manuscriptreceived20February1995ThecrystallizationfeaturesofFe38Hi39Si10B13metallicglassunder100keVand6μA/cm2heliumionirradiationwithdifferentdosesarereported.ItisfoundthattheFe38Ni39Si10B13metallicglasscrystallizedundertheheliumionirradiationatthetemperaturelowerthantheordinarythermalcrystallizationtemperature.ThepreferentialprecipitationphaseisFeSi,andfollowedbytheeutecticphaseα-Fe.Thecriticaldosefortheformationofheliumbubblesinthematerialisaround5x10 ̄16/cm2.Thesensitivityofcrystallizationduetothetemperaturerisingunderheliumionirradiationandthemechanismofthesequenceofprecipitatedphasearebrieflydiscussed.Keywords:Fe38Ni39Si10B13,metallicglass,crystallization,helium,ionirradiationTheblisteringorflakingoffirstwallmaterialsinducedbyheliumionbombardment,whichisrelevanttothefirstwallsurfaceerosionandplasmacontamination,isacriticalproblemtobeconsideredinfusionengineering.Becauseofthefavourablyphysical,chemicalandotherproperties,especially,thebetterresistanceofblistering,metallicglassesareexpectedtobeapromisingcandidatematerialforthefirstwall.TyagiandNanderkarstudiedsystematicallytheblisteringphenomenaofsomemetallicglassmaterialsunderheliumionandprotonbombardmentwithvariousionenergy,ioncurrentdensityanddose,andfoundthecriticaldoseforblisteringofthesematerials[1-3].However,itisverysuspiciousthatmetallicglasseswillcrystallizeunderheliumionirradiationtolosetheiramorphouscharacter,whichwilldeterioratetheirproperties.GusevaandGordeevareportedthatFe40Ni40B20metallicglassbombardedbyheliumionwithenergyof40keVandionbeamcurrentdensitiesof5-40μA/cm2partiallycrystallizedbelowitsordinarythermalcrystallizationtemperature[4].ByusingXRDexamination,itwasfoundthatα-FeandM3B,M2BandMBwereprecipitated(whereM=FeandNi)underheliumionbombardmentwith5μA/cm2and100μA/cm2ioncurrentdensitiesrespectively.Nevertheless,TyagiandNanderkarfoundthatsomemetallicglassescrystallizedandsomedidnotundersameirradiatedparameters[1-3].Consequently,itisnecessarytoinvestigatetheirradiation-assisted-crystallizationfeatureofmetallicglassesbyheliumionirradiationfortheirapplicationinfusionengineering.Inpresentexperiment,thecrystallizationfeatureofFe38Ni39Si10B13metallicglassunderheliumionirradiationwithenergy100keVandvariousdosesintherangeof5×1016/cm2to1×1018/cm2,andthedistributionofheliumbubblesinmaterialaremeasuredbyusingtransmissionelectronmicroscope(TEM)andX-raydiffraction(XRD).1.ExperimentalApproachTheas-receivedFe-Ni-Si-Bmetallicglassribbonswith10mminwidthand0.2mminthicknessweresuppliedbyBeijingInstituteofMetallurgy.Thenominalcomposition(wt%)ofthematerialisNi47.37,Fe43.91,Si5.81andB2.91fromthechemicalanalysisandthecalculatedconstituentisFe38Ni39Si10B13.TheX-raydiffractogramofas-receivedmaterialdemonstratedthattheas-receivedmaterialhasagoodamoophouscharacter.Thetheimalcrystallizationprocessoftheas-receivedmaterialwastestedbydifferentialthermalanalysis(DTA).Theordinarythermalcrystallizationtemperaturewasdeterminedtobeabout490℃.Rectangularsampleswithanareaof1×2cmanddiscsampleswith3mmindiameterwereemployedrespectivelyforXRDandTEMexperiments.ThesamplesforXRDweremechanicallypolishedtomirrorsurfaee.Ontheotherhand,formakingTEMsamples,thepiecescutfromtheribbonwerethinnedto30μmthicknessfirst,thenpunchedout3mmdiscs,electrothinnedinamixedsolutionof10%perchloricacidand90%ethanolandfinally,thediscswereionmilledtoextendthethinarea.HeliumionirradiationofsampleswascarriedoutonTS51-200/ZKionimplanterinChinaInstituteofAtomicEnergy.ThesampleswerefixedonacopperholderwhichwascooledbyF-113coolant.Thevacuumintargetwasbetterthan3×10-3Paandthescanningareaofionbeamwasabout3×7cm.Thetemperatureridingofthesamplescausedbyionbeambombardmentwasmeasuredbythermalcouple.Undertheirradiationparametersofionbeamenergy100keVandionbeamcurrentdensity6μA/cm2,thetemperaturerisingofsampleswaslowerthan200℃.Theiondosesofimplantedsampleswerechosenfrom5×10 ̄16/cm2to1×10 ̄18/cm2inpresentexperiment.AJEOL-100CXTEMoperatedat100kVwasused.Thecalculatedmeanprojectrangeandrangestragghngofheliumionwithenergy100keVinthematerialwere306.9nmand85.5nmrespectively,whichwassimulatedbycodeTRIM86.2.Results2.1CrystallizationunderionirradiationTheselectedareadiffraction(SAD)patternsofun-irradiatedandirradiatedsamplesareshowninFig.l.Fortheun-irradiatedsample,thepatterniscomposedoftwoconcentricringswhichexhibitatypicalamorphousdiffractionfeature(Fig.la).Ontheotherhand,forirradiatedsamples,agroupofnewconcentricringsappearsonthebaseofamorphousdiffractionrings,whichmeanstheoccurrenceofpartialcrystallizationandtheformationofsomenewprecipitationphasesinoriginalamorphousmaterialsbyionirradiation.Withtheincreaseofiondose,theinitialamorpohousdiffractionringsbecomefainterandtheintensitiesofdiffractionringsprodueedbyprecipitatesdevelopehigher.Itisexpectedthatthecrystallizationinsamplesincreaseswiththeincreaseiniondose.Moreover,iftheiondoseislowerthan5×10 ̄17/cm2,thepatternsshowtypicalpolycrystallinediffractionfeaturewithrandomorientationandveryfinegrains(Figs.lbandlc),butfor1×10 ̄18/cm2iondose,somebrightspotsarise(Fig.ld),thismeansthatsomerelativelargegrainsformedinsampleunderirradiation.FromtheX-raydiffractogramofthesampleirradiatedbyheliumiontodoseof5×10 ̄17/cm2,thediffractionpoaksarestillamorpohousfeatureandnonewpeaks.Itispredictedthatthecrystallizationonlyoccursintheprojectedrangeofions.2.2AnalysisofprecipitationphaseFromindexingofdiffractionringsinFig.lbandFig.lc,theprecipitatephaseisanfcccrystallinestructure.InFig.ld,anadditionalbccphaseisfound(ring3,ring5andring8).Thecalculatedlatticeparametersforprecipitatephasesundervariousiondosesareasfollows:5×1016/cm2a=0.412nm(fcc)l×1017/cm2a=0.42lnm(fcc)5×1017/cm2a=0.428nm(fcc)l×1018/cm2a=0.478nm(fcc)a=0.292nm(bcc)UsingASTMindex,itisidentifiedthatthebccphaseisα-Fe(a=0.2866nm).Todeterminethefccprecipitatephase,weinspectedallcompoundswithfcccrystallinestructurecomposedofelementsFe,Ni,SiandB,foundthatthreecompoundsFeSi(a=0.446nm),FeNi3(a=0.353nm)andFe3Si(a=0.564nm),butthemostfavourablecompoundwasFeSi.Therefore,itisassumedthatthepreferentialprecipitatephaseisFeSi,andisfollowedbytheeutectcphaseα-Feundertheheliumionirradiation.2.3HeliumbubbledistributionThemorphologiesofheliumbubblesformedbyagglomerationofimplantedheliumionsareshowninFig.2.Thesmallblackdotspresentbubblesunderbrightfieldwiththeunderfocusingoperation.FromFig.2,itisrevealedthatbubbleslowerthedensity,butinflateinthedimensionwiththeincreaseiniondose.Moreover,underthehigherdosethebubblesjoinedtogether.Fig.3plotsthechangesofdensitiesanddiametersofbubbleswiththeiondose.ItisevidentthatthecriticaldosetoformbubblesinFe38Ni39Si10B13islowerthan5×1016/cm2,whichisslightdifferentfrom1×1017/cm2reportedbyTyagi[1].3.DiscussionAstheresultsreportedbyGusevaandGordeeva[4],theheliumirradiationcantrulybringonthepartialcrystallizationinmetallicglassFe38Ni39Si10B13belowitsordinarythermalcrystallizationtemperature.GusevaandGordeevaconfirmedthattheprecipitatesinFe40Ni40B20wasα-Fephaseunderheliumionirradiationof40keVenergyand5μA/cm2currentdensity,inwhichthetemperaturerisingofthesampleswaslowerthan200℃.Howerve,inpresentexperiment,thoughα-Fephaseisdetermined,notraceofM3B,M2BandMBprecipitatephaseisobserved,whichwasreportedbyaboveauthorsunderirradiationwithenergyof40keVandioncurrentdensityof30μA/cm2.Inaddition,theprecipitationprocessinpresentexperimentissomewhatdifferentfromtheprecipitationprocessreportedbyaboveauthors,thepreferentialprecipitationphaseisFeSi,andfollowedbytheeutecticphaseα-Fe.CrystallizationofamorphousFe40Ni40B20wasnotobservedbyTyagi,whichwasthesamematerialasthatusedbyGusevaandGordeeva,undertheirradiationwith100keVionenergyand30μA/cm2ioncurrentdensity[3].Itmayrelatetothetemperaturerisingofsamplesorsomethingelse.Accordingtothecomparisonandanalysis,itmaybeconcludedthatthecrystallizationofmetallicglassesisverysensitivetothetemperaturerisinginsamplescausedbyionbeamirradiation.ThereasonofthepreferentialphasetobeFeSiandfollowedα-Femaybethatinanamorphousmaterial,themetalloidelementsshouldkeepatthetotalcontentsabove20at%,otherwisesomeelementsorcompoundswillprecipitatetoremainthebalanceofchemicalcomposition.Therefore,astheprecipitationofFeSianddeclineofSicontentsinasample,FeandNimayprecipitateasaneutecticphaseaccordingtoaboveidea.Inthisexperiment,Feprecipitatedfirstly.ThedifferenceoflatticeparametersbetweenexperimentaldataandASTMstandarddatamayresultsintheexistencesofNiandBetcandincompletecrystallizationinsample.Thegeneralviewpointforirradiation-assisted-crystallizationofmetallicglassbelowtheirthermalcrystallizationtemperatureisthedisplacementdamagesinducedbycollosion-cascadebetweenincidentionsandtargetatoms.Thedisplacementdamagesprovidethenucleatingcentresandtheirradiation-assistedmigrationincreasesthecrystallizeddrivingforce,butnodirectrelationshipbetweenheliumandcrystallization.Thegrowthofagrainiscloselyattributedtothediffusionofneighbouringatomstothegrowingnucleus,whichisreliedonthetemperatureextremely,accordingly,thecrystallizationofmetallicglassisverysensitivetothetemperaturerisingfromionbeambombardmentinanirradiatedsample.4.Summary(l)TheFe38Ni39Si10B13metallicglasswillcrystallizebelowitsordinarythermalcrystallizationtemperatureunderheliumionirradiationwith100keVenergyand6μA/cm2ionbeamcurrentdensity.(2)ThepreferentialprecipitationphaseofthemetallicglassisFeSi,andfollowedbyaneutecticphaseα-Fe.(3)Thecriticaldoseformingheliumbubblesinthemetallicglassisabout5×1016/cm2,whichisslightlylowerthanthedosereportedbyTyagi.(4)Theirradiation-assisted-crystallizaofametallicglassesisverysensitivetothetemperaturerisingcausedbyionbeambombardmentinanirradiatedsample.Acknowledgements─TheauthorswouldliketothankthecolleaguesofIonImplantationGroupinChinaInstituteof.AtomicEnergy.forhelpinginsampleirradiation,alsotoProfe

关键词: : Fe38Ni39Si10B13 , null , null , null , null

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