《透射电镜样品的制备：干粉法-液体》由会员分享，可在线阅读，更多相关《透射电镜样品的制备：干粉法-液体（27页珍藏版）》请在金锄头文库上搜索。
1、 透射电镜样品的制备 1 分散晶体 粉末样 干粉法液体法 2 萃取复型 用于观察断口形貌 第二相大小分布 点阵类型 3 薄膜平面膜截面膜方法 超薄切片减薄人工 电化学减薄或离子减薄聚焦离子束 选区电子衍射 阿贝衍射原理 倒易点阵与正点阵 d110 g110 b a r110 衍射几何条件 厄瓦球面 Thesizeofdiffractionpatterns 1 l ghkl L Rhkl R d lLWhenisqsmall electrondiffraction Rd lL diffractionconstant q Rhkl Rhkl Plottingandindexingofsinglec
2、rystalspotpatterns Whenqissmall electrondiffraction thereflectionspherecutsa2Dreciprocalplane S0 l k0 S l k ghkl hkl 000 相机长度 Rhkl 图3 9Al3Ni型正交相Al74 8Fe1 5Ni23 7的选区电子衍射花样 Plottingandindexingofsinglecrystalspotpatterns Indexing theplanenormal uvw andatleastonelowindexspot hkl normallytwospots withhu
3、kv lw 0 S0 l k0 S l k ghkl hkl 000 相机长度 Rhkl Plottingandindexingofsinglecrystalspotpatterns Foraknownsubstancebutunknownorientation atableofinterplanarspacingsdisneeded a Choosethreespotssuchash3k3l3 h1k1l1 h2k2l2 b Measurethedvalues andthusdeterminetheindices c Bytrialanderroraconsistentsetofindice
4、sischosensuchthath3k3l3 h1k1l1 h2k2l2 d uvw thezoneaxis isobtainedbyanytwovectors e g R1 R2 S0 l k0 S l k ghkl hkl 000 相机长度 Rhkl h1k1l1 h2k2l2 h3k3l3 uvw R1 R2 Plottingandindexingofsinglecrystalspotpatterns Example anfcccrystalwitha 0 58nm d a h2 k2 l2 1 2 AdiffractionpatternisshownbelowwithR1 R2 8
5、96mm R1 R2 109 5 Ll 3 0nm mm a ChoosethreespotsR1 R2 R3 R3 R1 R2 b d1 d2 Ll R1 0 335nm 111 c Aconsistentsetofindicesis002 111 1 11 d R1 R2 1 10 thezoneaxis晶带轴 R1 R2 109 5 R3 也可以直接查表 PARAMETERSA 5 8000B 5 8000C 5 8000 AF 90 000BT 90 000GM 90 000NUVW 3NSY 1NL 1SY 1 CUBIC 2 TETRA 3 ORTH 4 HEX 5 MONO 6
6、TRICLT 1 F 2 I 3 C 4 B 5 A 6 P 7 R KUVWH1K1L1H2K2L2R2 R1R3 R1FAId1d2111102 2 2021 0001 000120 002 0512 0512110 11 1 1111 0001 15570 533 3493 34931000 2000 21 0001 41490 002 9002 90043322 2011 31 1731 54190 002 0511 74952212 2002 41 5811 581108 432 0511 29762111 1 102 21 6331 91590 003 3492 051731000
7、 2 13 11 6581 65872 452 9001 74983110 222 4 21 7321 73273 222 0511 184932202 2 4242 1212 121103 632 051 967103312 2020 62 2362 23677 082 051 9171121000 2 2402 2362 44990 002 9001 297123211 1 1 13 32 5172 58297 613 3491 3311332000 2 4603 6063 74290 002 900 804 R2 R1 109 5 111 111 002 110 R3 220 Index
8、ingofsinglecrystalspotpatternsfromanunknownphase ProcedureSurveytheliteraturetocollectinformationofpossiblephases ThreepossibleroutestoreachitsfullindexingCalculatedspacingsandcomparewithstandardpowderXRDdata MeasureR2 R1 R2 R1 andcomparewithtablesinarchives Tryacubicphase Usedoubletiltingtodetermin
9、edirectlythe3Dreciprocallattice Ingeneralthreeindependentpatternsarenecessarytodetermineareciprocalstructure R1 R2 109 5 R3 Adiffractionpatternisshownontheright R1 R2 14 4mm R1 R2 109 5 Ll 3 0nm mm StandardpowderXRDdata d1 d20 208d3 0 180d4 0 127 Cubicindexing CubicindexingChoosethreeshortestrecipro
10、calvectorsR1 R2 R3 R3 R1 R2 measuretheangleR1 R2 Calculated1 d2 R2 R1 2 R3 R1 2 Judgepossiblecombinationsofhkl Ingeneralthreeindependentpatternsarenecessarytodeterminethereciprocalstructure R1 R2 109 5 R3 Adiffractionpatternisshownontheright R1 R2 14 4mm R1 R2 109 5 Ll 3 0nm mm d1d2 R2 R1 2 R3 R1 20
11、 2080 2081 1 155 2 4 3 Cubicindexing R1 R2 109 5 R3 R1 R2 14 4mm R1 R2 109 5 Ll 3 0nm mm d1d2 R2 R1 2 R3 R1 20 2080 2081 1 155 2 4 3 8 6111111111 111002 111 Cubicindexing R1 R2 109 5 R3 R1 R2 14 4mm R1 R2 109 5 Ll 3 0nm mm d1d2 R2 R1 2 R3 R1 20 2080 2081 1 155 2 4 3111 1 11 1 11 111002 111cF a 0 36n
12、m 奥氏体铁 Self consistencyofindices 111 1 11 002 Anglecheck 111 1 11 109 5 Latticeconstantcheck a d111 3 0 360nmTwomorepatternsarenecessarytoassurethephaseidentification Exercises indexthefollowingpatternsincubicschemes Notethattheremaybemorethanonepossibilitiesforeachpatterns Givethecorrespondinglatti
13、cetypesandconstants R1 R2 R3 R1 R2 R3 23 6mm R1 R2 120 Ll 3 0nm mm d1d2 R2 R1 2 R3 R1 2latticeconstant0 1270 12711110 101 101 110011 110cP cI0 18nm220 202 202 220022 220cF0 36nm 111 Exercises indexthefollowingpatternsincubicschemes Notethattheremaybemorethanonepossibilitiesforeachpatterns Givethecor
14、respondinglatticetypesandconstants R1 R2 R3 R1 R2 16 7mm R1 R2 90 Ll 3 0nm mm d1d2 R2 R1 2 R3 R1 2latticeconstant0 1800 18011100010010 100110 1000 180nm1 10110110 1 10200 1 100 255nm200020020 200220 2000 360nm 001 Exercises indexthefollowingpatternsincubicschemes Notethattheremaybemorethanonepossibi
15、litiesforeachpatterns Givethecorrespondinglatticetypesandconstant R1 R2 R3 R1 16 7mm R2 R3 27 5mm R1 R2 107 5 Ll 3 0nm mm d1d2 R2 R1 2 R3 R1 20 1800 10911 411 4002 31 1 31 1 002 311 002cF 0 36nm 130 Exercises indexthefollowingpatternsincubicschemes Notethattheremaybemorethanonepossibilitiesforeachpa
16、tterns Givethecorrespondinglatticetypesandconstants R1 R2 R3 R1 16 7mm R2 23 6mm R1 R2 90 Ll 3 0nm mm d1d2 R2 R1 2 R3 R1 2a0 1800 12723001 110 110 001 111 001cP0 18nm1 10002002 1 101 12 1 10cI0 255nm002 220 220 002 222 002 110 Usedoubletiltingtodeterminedirectlya3Dreciprocallattice 000 000 a1 a2 a3 000 100 010 001 010 001 100 a1 26 56 120 110 210 120 001 a2 18 43 110 110 001 111 a3 18 43 010 000 001 100 101 Usedoubletiltingtodeterminedirectlya3Dreciprocallattice 图3 4六角相Al5FeNi的选区电子衍射花样Figure3 4S
