725-中子散射在工程材料研究中应用-织构与应力测量-王沿东

中子散射在工程材料研究中应用：织构与应力测量,王沿东北京科技大学,主要内容,中子衍射在工程材料应用实例：应力与织构科学问题原位测量与表征方法(中子散射与高能X射线衍射)研究的最新进展金属形变（多相材料、复杂形变过程）金属超弹性行为研究新进展金属磁致形状记忆合金研究总结,中子衍射在工程材料研究中应用,中子衍射在工程材料研究进展,中子衍射在工程材料研究进展,Residualstressstandardusingneutrondiffraction(RESTAND),工程材料应力测量,大型结构工程部件（飞机、航空器、航母等），除承受宏观应力外，存在微观应力。,微观应力是材料损伤行为、材料功能行为的最直接相关的微结构单元（状态）；微观应力准确测量与分析是其精确设计与控制的前提；目前通用的微观力学模拟方法仅适合确定小应变（5%）状态下的微观应力。,大型工程部件应力测量,金属形变行为核工业,铀的形变研究,ResearchatLosAlamosNationalLaboratory,焊接锆的残余应力研究,形变过程织构演化机械加工业,Deep-drawing,AA3104withacubictexturecomponentleadingtoearsduringdeep-drawing,功能行为国防、交通工业,CrystallographictextureandstressisacrucialmicrostructuralfeaturetocontroltheperformancepropertiesinShapeMemoryAlloy(SMA),Electronics,Attitudecontrolsystemofastationarysatellite:Ashapememoryspringopensandclosesthesolarcells,Transportation,Automaticoilvalveadjustingequipment,SonarSystemsinMarineApplications,新一代磁感应器件,利用马氏体相变过程产生马氏体（孪晶）变体的择优选择及逆相变过程中母相奥氏体晶体结构恢复,多晶金属形变过程研究,TEM下发现位错,1960-1990H.J.Bunge,1990-2000Adams/Holden,2000-？,XRD极图测量晶体取向变化（ODF）织构模拟（简单模型）,EBSP微取向的测量中子散射微应力测量先进织构模拟方法,先进中子散射微应力测量同步辐射高能XRD多维多尺度应力场理论,StrainPFs,?,真实应力状态真实环境时间分辨空间分辨,织构测量、分析与模拟,Texturemeasurementsconstantwavelength,Deformedstainlesssteel,MeasuredatRESTintheNFL,Shapeofsamples,Cubicorquadratic,Cylinder,Pyramidalorspherical,CourtesytoBrokmeier,Almostnoabsorptioncorrectionisrequired!,Measurementsbypulsedneutronsource,GeneralPurposePowderDiffractometer(GPPD)inIPNS,Incidentbeam(neutron),KappaGoniometry,Detectors,Measurementsbypulsedneutronsource,High-PressurePreferredOrientation(HIPPO)neutrondiffractometer,Fulltexturemeasurements,In-situheatingat950CforbccZr,Firstcycle,Secondcycle,CourtesytoR.H.Wenk,应力测量、分析与模拟,应力研究的科学问题,Macro-stressfields(polycrystalline),StressP,z=(d-d0)/d0,Z,Y,X,y=(d-d0)/d0,HookesLaw:z=x/E-(y+x)/Ex=x/E-(x+z)/Ey=y/E-(x+z)/E,Assumingisotropicandelastic,hkl,Measurementsoflatticestrains,Strainandstressdistributions,Diffractionpeaks,III,h1k1l1,h2k2l2,I,II,TypeIIstress,TypeIstressormacro-stress,TypeIIIstress,Direction11,Micro-stress,TypeIIstress-nonlinearlatticestrains,Forthemacro-stressanalysis,non-linearrelationshipbetweenthed-spacingandsin2isoftenfoundinsomepolycrystallinematerials(evenwithouttexture):,TheinfluenceoftextureonthediffractionelasticconstantsTheexistenceoftypeIIstress(intergranularstress),whichisdependentongrainorientation(grain-orientation-dependentstress),IFsteelin-situloading,CarriedoutinAPS,ArgonneNationalLab.,IntergranularstressMicro-stress,TheoreticalapproachModelingofthestress/strainstateofindividualgrainsusingvariousmodels,suchasTaylor,self-consistent(SC),finiteelementmethod(FEM)ExperimentalapproachAcontinuefunction,stressorientationdistributionfunction(SODF),isdefinedasameanfieldofgrainorientationdependentstressoverEulerspace;Similartotextures,SODFcanbeexpressedbyalimitednumberofseriescoefficents;DeterminationoftheseriescoefficientsofSODFdirectlyfromthemeasuredlatticedistributions(strainpolefigures,SPFs).,IntergranularstressMicro-stress,FiniteElementMethod(FEM)onthescaleofgrains,Whyisthereexistenceofintergranularstress,Slipsofdislocationsandrotationofgrains,Mappingthree-dimensionalstressfields,offersthepossibilityforavarietyofin-situinvestigations(e.g.enginestudies,in-situweldingandcutting,in-situprocessingorstress-relieving).,Macro-stressfield,中国研究平台,中国工程物理研究院中国原子能研究院上海光源,脉冲中子源（东莞，中科院物理研究所在建）,各种应力测量方法的比较,基本科学问题,多维多尺度应力场构建与测量,三维空间+三维点阵(倒易)空间应变场测量;三维空间宏观应力场分布模拟;材料各向异性多(单)晶体本构方程建立;多尺度微观应变场的描述与模拟;晶体取向（织构）与各类应力交互作用；材料损伤与各类应变场的定量关联。,研究方法与特色,动态测量；包含形变、相变过程;多尺度模拟（FEM与Self-Consistent）;中子与同步辐射高能XRD、微束衍射相互配合。,12mm厚板实样测量应力分布,焊接工件,退火工件,12mm,入射中子束,反射中子束,测量与FEM模拟实例,模拟,测量,应力测量装置基于反应堆中子源,In-situloadingexperiments,LosAlamosNeutronScatteringCenter,SpectrometerforMaterialsResearchatTemperatureandStress(SMARTS),应力测量装置基于脉冲中子源,同步辐射高能X射线衍射,In-situheatinganddeformation,1-IDand11-ID-C,APS,ArgonneNationalLaboratory,80-115keV,Samplestage,同步辐射源上的强磁场下结构表征装置研制（美国Argonne国家实验室），可同时进行强磁、应力及温度场耦合的原位试验。,11-ID-CatAPS,Beam-line,High-energyX-ray(E=105keV,=0.1),Beamsize0.10.1mm,K-BFocusingmirrors,CCD,Samplestage,shutter,slit,telescope,differentialaperture(wirescan,200mabovesamplesurface),3-DX-RayStructuralMicroscopeatExperimentalHutch34-ID-E,空间分辨率：微米,WhitebeamLaue,金属形变过程,StrainPoleFiguresandSODFforAusteniteStainlessSteel,Y.D.Wanget.al.ActaMater.50(2002),p.1717,Developmentofresidualstressesinstainlesssteelduringfatigue,Latticestraindistributioninstainlesssteel,Grain-orientation-dependentresidualstressesinstainlesssteelduringfatigue,StressalongLD,StressalongTD,5,159cycles(micro-cracksjustproduced),5,506cycles(micro-crackspropagated),7,872cycles(specimenreachesfailure),Storedenergyinstainlesssteelduringcyclicaldeformation,NatureMaterials2(2003),p.101-106,Y.D.Wang,et.al.(asArticle),Twokindsofstoredenergy:Intergranularstoredenergycausedbythemismatchstressofgrain-interactions;Intragranularstoredenergycausedbythepinneddislocationsinsidegrains;,形变双相合金微观与宏观应力分布,N.Jia,R.LinPeng,Y.D.Wang,et.al.ActaMater.54(2006),3907-3912.N.Jia,R.LinPeng,Y.D.Wang,et.al.ActaMater.56(2008),782-783.,Fe-25Cr-7Ni-4Mo-1.2Mn-0.3Ninwt%58%austenite()and42%ferrite(),形变过程多相合金微观应力与织构,Y.D.Wang,et.al.ActaMater.57(2009),3965-3977.,Transformation-induced-plasticity(TRIP)assisted-steel5%austenite(A)+19%Bainite(B)+42%ferrite(F),Meas.texture,Sim.texture,金属覆层材料中微应力的交互作用,利用同步辐射高能X射线的微束衍射方法，揭示纯金属覆层材料中沿生长方向存在晶粒间应力交互作用，该应力大于平面内方向的应力。,改变人们对覆层中应力的传统认识,Y.D.Wang,et.al.Adv.Mater.,17(2005),1221,G.J.Fan,Y.D.Wang,et.al.,纳米金属微观应力分布,G.J.Fan,L.F.Fu,Y.D.Wang,et.al.,纳米金属断裂过程,微束劳埃衍射研究纳米孪晶金属形变过程中退孪晶过程,In-situloading,劳埃衍射斑,Y.D.Wang,et.al.submitted,微束劳埃衍射研究纳米孪晶金属形变过程中退孪晶过程,形状记忆合金中的形状记忆与超弹性研究,什么叫记忆合金？,记忆合金就是能记住其初始形状的金属,当这种合金变形后当达到某个特定的温度时能恢复其原始形状.,记忆合金的形状记忆效应示意图,马氏体相变可由两种方式产生1.降低温度(冷却)热致马氏体2.施加应力应力诱发马氏体形状记忆行为也对应于两种模式:记忆效应温度变化-形状恢复超弹性(伪弹性)外力-形状恢复,传统记忆合金的超弹性效应示意图,GumMetals(GMs),力学性能：高强度、低弹模、超弹性、超塑性形变方式：无位错、无相变、没有孪晶,力学性能：高强度、低弹模挑战了传统的金属强度理论金属强度是由位错滑移阻力（）决定弹性模量（E）是与金属的结合键性质有关,(1)Thecriticalshearstresstoactuatetheglideofthecrystallographicline-defectscalleddislocations,i.e.,1/30(istheshearelasticmodulus).(2)TheYoungsmodulusE=2(1+)(isthePoissonsratio,n,varyingwithinanarrowrangefrom0.25to0.352).E60(1+),Y.W.Zhang,Y.L.Hao,R.Yang,ActaMater2001;59:3081,SpecifiedelasticpropertiesforTi-24Nb-4Zr-8Snsinglecrystalsundertensionandcompressionloading,LowYoungsmodulus(50GPa)andasymmetryintensileandcompressionNon-linearelasticbehaviorinelasticregionundertensionandcompressionExcellentductilitywithlowPoissonsratio,GMs的形变方式：无位错、无相变、没有孪晶“Nano-disturbance”non-crystallographicpartialdislocationswiththeBurgersvectorshavingnon-quantizedmagnitude(1/10fulldislocation)?,Twoothercasestoshownewmechanismsonsuperelasticbehaviorsofalloys,H.J.Maieret.al.ActaMater.56,2231(2008).,I.Karamanet.al.ActaMater.55,4253(2007).,CaseI:Whatistheatomicmechanismsonthetwo-stepsuperelasticityobservedinNi2MnGasinglecrystal?PMX5-layerMartensite?,Lowfieldmagnetizationasafunctionoftemperature,Atypical010Pzone-axis2Ddiffusescatteringpatternat300K,Ni2MnGasinglecrystal,MagnetizationtransformationinNi2MnGa,NewmechanismofsuperelasticbehaviorinNi2MnGa,Z.H.Nie,Y.D.Wang*,et.al.Appl.Phys.Lett.,97,171905(2010),Uniaxialstress-inducedrearrangementofnanodomainsinpremartensite,nano-scalestraindomains,X-raydiffractionatdifferenttemperatures,Dynamicmechanicalmeasurement,CaseII:strainglassystateforTi48.5Ni51.5Alloy,Y.WangandX.Ren,Phys.Rev.Lett.97,225703(2006),Itwasbelievedthatthealloyhavingtheheterogeneityinstraindomains,causedbydopingsomeextraatoms,maygeneratethestrain-glassystate,Y.WangandX.Ren,Phys.Rev.Lett.97,225703(2006),Thestress-straincurves,Insitux-raydiffractionevidenceforastructurechangeatdifferentstresses,MechanicalbehaviorofTi48.5Ni51.5alloywithstrain-glassy-state,Forstrainglass,thereexistsnospontaneousmartensitictransformation,yetmartensitecanbeinducedbystress.,TEMdiffractionpatternsofTi50Ni46Fe4andTi50Ni44Fe6alloysatdifferenttemperatures.(a)(c)Ti50Ni46Fe4and(d)Ti50Ni44Fe6,PhasediagramofTi50Ni50-xFexferroelasticsystem,D.Wang,andX.Renetal.ActaMaterialia58(2010)6206-6215.,TEMobservationtoshowacompletetemperaturecompositionphasediagramforelucidatingthepre-martensiticstate,martensiteandstrainglass.,TemperaturecompositionphasediagramofTi50Ni50-xFexalloys,AtransitionofsuperelasticbehaviorinNiCoFeGaalloy,Formationofnano-scalestraindomainsthroughCo-dopinginNiFeGaStress-inducedrearrangementofnano-scaledomainstochangethesuperelasticbehavior,Parentphase,Ms,Martensite,Sharphysteresis,Smoothhysteresis,FrozenStrainglass,UnfrozenStrainglass,Superelasticregion,Temperature(K),Ni55-xCoxFe18Ga27x(at.%),TemperaturecompositionphasediagramforNiCoFeGa,D.P.WangandY.D.Wang,EPL,98(2012)46004,金属相变研究铁磁形状记忆合金“记忆”行为,http:/materiaali.tkk.fi/en/PhysicalMetallurgy/English/mainpage.html,A.Sozinovetal.,Appl.Phys.Lett.,(2002),14modulatedsinglecrystal,Stressinducedstrain,Magneticfieldinducedstrain,Motionoftwinboundaries,R.Kainumaetal.,Nature(2006),Magneticfieldinducedphasetransition,Ni45Co5Mn36.7In13.3,L21Heuslerstructure,Background,FerromagneticShapeMemoryAlloys,Ni48.8Mn29.7Ga21.5,VS,MagneticfielddrivenshapememoryLargeoutputofstrainorstressFastresponseunderhighfrequency,9%101MPa,3%102MPa,AdvanceforNeutronDiffraction,Ni2MnGaalloy,MemoryofMacro-TexturesinNi48Mn25Ga22Co5(Ex-Situ),Initialstate,Afterdeformation,HeatingtoaboveMsandcoolingtoroomtemperature,(a),(b),(c),D.Y.Cong,Y.D.Wang,et.al.Metall.Trans.A,37A(2006),1397,In-SituStudiesforMemoryofMacro-Textures,Y.D.Wang,et.al.Phy.Rev.B,75(2007),174404,Ni48Mn25Ga22Co5,TransitionKineticsandPartitioningofVariants,Ni48Mn25Ga22Co5,Landautheory,TexturesinMartensiteforNi48Mn25Ga22Co5,=0MPa(1thcycle),Changeofinversepolefiguresforloadingdirectionafterrepeatingphasetransformationunderdifferentstresses,=0MPa(2thcycle),=60MPa,