电子背散射衍射EBSD

ZhengminLiZhengminLiElectronElectronBackScatteredBackScatteredDiffractionDiffraction))EBSDEBSDZhengminLiZhengminLi1.1.••EBSDEBSDZhengminLiZhengminLiaabbcc9090aabbcc90909090aabbcc=====90=90aabbcc9090a=b=ca=b=c====9090a=ba=bcc===90=90120120aabbcc9090ZhengminLiZhengminLi••••••EBSDEBSDEBSDEBSDZhengminLiZhengminLi••19721972VenablesVenablesHarlandHarlandSEMSEM30CM30CM(EBSP)(EBSP)••20208080DingleyDingleyZhengminLiZhengminLi20209090SEMSEM(ElectronBack(ElectronBack--scatteringPatternsscatteringPatternsEBSP)EBSP)(ElectronBackscatter(ElectronBackscatterDiffractionDiffractionEBSD)EBSD)(OrientationImaging(OrientationImagingMicroscopyMicroscopyOIM)OIM)ZhengminLiZhengminLiEBSDEBSD((88//))((0.020.02μμmm0.50.5°°))ZhengminLiZhengminLi2.2.EBSDEBSD••EBSDEBSDSEMSEM(())EulerEuler((ϕϕ11,,ϕϕ,,ϕϕ22))ZhengminLiZhengminLiZhengminLiZhengminLi••SEMSEM(())••XX••••22ooZhengminLiZhengminLi(())ZhengminLiZhengminLi,,,(),,(),,,θλsin2dn=ZhengminLiZhengminLiEBSDGeometryZhengminLiZhengminLiKikuchilineKikuchilineZhengminLiZhengminLiAdiffractionpatternfromnickelcollectedat20kVacceleratinAdiffractionpatternfromnickelcollectedat20kVacceleratingvoltagegvoltageZhengminLiZhengminLiABCABCXXYYZZ3a3a2b2b6c6cXXYYZZaabbcc332266223311231231ZhengminLiZhengminLi••••••[[uvwuvw]]ABABOOOP,OP,110110,,ABAB[110][110]OBOB111111[111][111]OCOCCC100100[100][100]ODOD[010],OA[010],OA[001][001]11--66[100][100],,100100ZhengminLiZhengminLihklZhengminLiZhengminLiThenickelcrystalunitcellsuperimposedonthediffractionpatternintheorientationwhichgeneratesthispattern.Thecrystalplanesarelabelledwhichcorrespondtothe(2-20)and(020)Kikuchibandsinthediffractionpattern.ZhengminLiZhengminLi••w2lnl/d•The(200)planedThe(200)planed--spacingiswiderthanthe(2spacingiswiderthanthe(2--20)planesothe20)planesotheKikuchibandsfrom(200)planesarenarrowerthanthosefrom(2Kikuchibandsfrom(200)planesarenarrowerthanthosefrom(2--20)planes.20)planes.ZhengminLiZhengminLi••Thesymmetryofthecrystalisshowninthediffractionpattern.Thesymmetryofthecrystalisshowninthediffractionpattern.Forexample,Forexample,fourfoldsymmetryisshownaroundthe[001]directionbyfoursfourfoldsymmetryisshownaroundthe[001]directionbyfoursymmetricallyymmetricallyequivalent013zoneaxes.equivalent013zoneaxes.ZhengminLiZhengminLiZhengminLiZhengminLi(TEM)TEMSEMEBSD50nmSiZhengminLiZhengminLi••••ZhengminLiZhengminLi3.3.SEMEBSDEBSD70°EBSDZhengminLiZhengminLi2-2EBSPEBSP1.2.3.4.;5.1Indexx,yφ1Φφ2MADBC…12345ZhengminLiZhengminLi••7070••••CCDCCD••••SEMSEM••••DiagramoftheprincipalcomponentsofanEBSDsystemZhengminLiZhengminLiFig.2AphotographtakeninsideanSEMchambershowingthetypiFig.2AphotographtakeninsideanSEMchambershowingthetypicalcalexperimentalarrangementforEBSDexperimentalarrangementforEBSDabeamofelectronsisdirectedatabeamofelectronsisdirectedatapointofinterestonatiltedapointofinterestonatiltedcrystallinecrystallinesampleintheSEMsampleintheSEMZhengminLiZhengminLiZhengminLiZhengminLiZhengminLiZhengminLiZhengminLiZhengminLiMonteCarlosimulationofelectrontrajectoriesinaSitargetZhengminLiZhengminLi••BackgroundBackgroundOriginalpatternBackgroundsubtractionBackgrounddivisionZhengminLiZhengminLiEBSDEBSDEBSDEBSDEulerZhengminLiZhengminLi•μμZhengminLiZhengminLi••••4.EBSDEBSDZhengminLiZhengminLiEBSD10mm12004000ZhengminLiZhengminLiZhengminLiZhengminLiZhengminLiZhengminLi12127070HClOHClO44:CH:CH33OHOH20ml:80ml20ml:80ml--202045456060SEMSEMEBSPEBSPEBSDEBSD50nm50nmEBSDEBSDZhengminLiZhengminLiNi)Ni)ZhengminLiZhengminLi••ZhengminLiZhengminLi5.EBSDApplication5.EBSDApplication(1)(1)••InEBSDInEBSDZhengminLiZhengminLi••PointanalysisofgrainsinsteelshowingthediffractionPointanalysisofgrainsinsteelshowingthediffractionpatternandcalculatedcrystalorientationpatternandcalculatedcrystalorientationZhengminLiZhengminLi(2)(2)••ZhengminLiZhengminLiOIM(OrientationOIM(OrientationImagingMicroscope)ImagingMicroscope)ZhengminLiZhengminLiZhengminLiZhengminLiZhengminLiZhengminLi•Normaldirectioncrystalorientationmap(ZhengminLiZhengminLiRollingdirectioncrystalorientationmapRollingdirectioncrystalorientationmapZhengminLiZhengminLi••TransversedirectioncrystalorientationmapTransversedirectioncrystalorientationmapZhengminLiZhengminLi••Thecrystalorientationatthispointis[2Thecrystalorientationatthispointis[2--34]paralleltothesample34]paralleltothesamplerollingdirection(RD)andthe(92rollingdirection(RD)andthe(92--3)planenormalparalleltothe3)planenormalparalleltothesamplenormaldirection(ND).samplenormaldirection(ND).ZhengminLiZhengminLi(3)(3)ZhengminLiZhengminLiZhengminLiZhengminLi••Mapshowinggrainpositions.AllneighbouringpointswithinagrMapshowinggrainpositions.Allneighbouringpointswithinagrainainhaveamisorientationlessthan3haveamisorientationlessthan3ZhengminLiZhengminLi••HistogramofgrainsizesfromdatainpreviousfigureHistogramofgrainsizesfromdatainpreviousfigureZhengminLiZhengminLi(4)(4)••ZhengminLiZhengminLi••••••••::ZhengminLiZhengminLi••SamplenormaldirectionSamplenormaldirectionSamplerollingdirectionSampletransversedirectionZhengminLiZhengminLi(5)(5)••XX38.6%38.6%60.7%60.7%ZhengminLiZhengminLiZhengmi