Preface ...................................................... xiii
1. Introduction ................................................. 1
1.1 X-Ray Technology and Its Brief History .................. 1
1.2 Geometry of Crystals .................................... 2
1.2.1 Crystal Lattice and Symmetry ..................... 3
1.2.2 Lattice Directions and Planes .................... 4
1.2.3 Atomic Arrangement in Crystal Structure .......... 9
1.2.4 Imperfections in Crystal Structure .............. 11
1.3 Principles of X-Ray Diffraction ........................ 13
1.3.1 Bragg Law ....................................... 13
1.3.2 Diffraction Patterns............................. 14
1.4 Reciprocal Space and Diffraction ....................... 16
1.4.1 Reciprocal Lattice .............................. 16
1.4.2 The Ewald Sphere ................................ 18
1.4.3 Diffraction Cone and Diffraction Vector Cone .... 19
1.5 Two-Dimensional X-Ray Diffraction ...................... 21
1.5.1 Diffraction Pattern Measured by Area Detector ... 21
1.5.2 Two-Dimensional X-Ray Diffraction System and
Major Components ................................ 22
1.5.3 Summary ......................................... 23
References.............................................. 25
2 Geometry Conventions ........................................ 28
2.1 Introduction............................................ 28
2.1.1 Comparison Between XRD2 and Conventional XRD .... 29
2.2 Diffraction Space and Laboratory Coordinates ........... 30
2.2.1 Diffraction Cones in Laboratory Coordinates ..... 30
2.2.2 Diffraction Vector Cones in Laboratory
Coordinates...................................... 33
2.3 Detector Space and Detector Geometry.................... 35
2.3.1 Ideal Detector for Diffraction Pattern in 3D
Space ........................................... 35
2.3.2 Diffraction Cones and Conic Sections with Flat
2D Detectors .................................... 36
2.3.3 Detector Position in the Laboratory System ...... 37
2.3.4 Pixel Position in Diffraction Space—Flat
Detector ........................................ 37
2.3.5 Pixel Position in Diffraction Space—Curved
Detector ........................................ 39
2.4 Sample Space and Goniometer Geometry ................... 42
2.4.1 Sample Rotations and Translations in Eulerian
Geometry ........................................ 42
2.4.2 Variation of Goniometer Geometry ................ 44
2.5 Transformation from Diffraction Space to Sample
Space .................................................. 46
2.6 Summary of XRD2 Geometry ............................... 49
References ............................................. 49
3 X-Ray Source and Optics ..................................... 51
3.1 X-Ray Generation and Characteristics ................... 51
3.1.1 X-Ray Spectrum and Characteristic Lines ......... 51
3.1.2 Focal Spot and Takeoff Angle .................... 53
3.1.3 Focal Spot Brightness and Profile ............... 53
3.1.4 Absorption and Fluorescence ..................... 55
3.2 X-Ray Optics ........................................... 56
3.2.1 Liouville's Theorem and Fundamentals ............ 56
3.2.2 X-Ray Optics in a Conventional Diffractometer ... 59
3.2.3 X-Ray Optics in Two-Dimensional
Diffractometer .................................. 62
3.2.4 The β-Filter .................................... 66
3.2.5 Crystal Monochromator ........................... 68
3.2.6 Multilayer Mirrors .............................. 70
3.2.7 Pinhole Collimator .............................. 76
3.2.8 Capillary Optics ................................ 79
References ............................................. 83
4 X-Ray Detectors ............................................. 85
4.1 History of X-Ray Detection Technology .................. 85
4.2 Point Detectors in Conventional Diffractometers ........ 88
4.2.1 Proportional Counters ........................... 88
4.2.2 Scintillation Counters .......................... 89
4.2.3 Solid-State Detectors ........................... 90
4.3 Characteristics of Point Detectors ..................... 91
4.3.1 Counting Statistics ............................. 91
4.3.2 Detective Quantum Efficiency and Energy Range ... 93
4.3.3 Detector Linearity and Maximum Count Rate ....... 94
4.3.4 Energy Resolution ............................... 96
4.3.5 Detection Limit and Dynamic Range ............... 98
4.4 Line Detectors ........................................ 100
4.4.1 Geometry of Line Detectors ..................... 100
4.4.2 Types of Line Detectors ........................ 103
4.4.3 Characteristics of Line Detectors .............. 104
4.5 Characteristics of Area Detectors ..................... 107
4.5.1 Geometry of Area Detectors ..................... 108
4.5.2 Spatial Resolution of Area Detectors ........... 112
4.6 Types of Area Detectors ............................... 114
4.6.1 Multiwire Proportional Counter ................. 115
4.6.2 Image Plate .................................... 117
4.6.3 CCD Detector ................................... 118
4.6.4 Microgap Detector .............................. 122
4.6.5 Comparison of Area Detectors ................... 127
References ................................................ 130
5 Goniometer and Sample Stages ............................... 133
5.1 Goniometer and Sample Position ........................ 133
5.1.1 Introduction ................................... 133
5.1.2 Two-Circle Base Goniometer ..................... 134
5.1.3 Sample Stages .................................. 135
5.1.4 Sequence of the Goniometer Axes ................ 136
5.2 Goniometer Accuracy ................................... 138
5.2.1 Sphere of Confusion ............................ 138
5.2.2 Angular Accuracy and Precision ................. 141
5.3 Sample Alignment and Visualization Systems ............ 143
5.4 Environment Stages .................................... 145
5.4.1 Domed High Temperature Stage ................... 145
5.4.2 Temperature Stage Calibration .................. 146
References ................................................ 149
6. Data Treatment ............................................ 151
6.1 Introduction .......................................... 151
6.2 Nonuniform Response Correction ........................ 151
6.2.1 Calibration Source ............................. 152
6.2.2 Nonuniform Response Correction Algorithms ...... 154
6.3 Spatial Correction .................................... 156
6.3.1 Fiducial Plate and Detector Plane .............. 156
6.3.2 Spatial Correction Algorithms .................. 158
6.4 Detector Position Accuracy and Calibration ............ 163
6.4.1 Detector Position Tolerance .................... 163
6.4.2 Detector Position Calibration .................. 165
6.5 Frame Integration ..................................... 167
6.5.1 Definition of Frame Integration ................ 167
6.5.2 Algorithm of Frame Integration ................. 170
6.6 Lorentz, Polarization, and Absorption Corrections ..... 175
6.6.1 Lorentz ........................................ 175
6.6.2 Polarization ................................... 176
6.6.3 Air Scatter and Be-Window Absorption ........... 180
6.6.4 Sample Absorption .............................. 182
6.6.5 Combined Intensity Correction .................. 188
References .................................................. 189
7 Phase Identification ....................................... 191
7.1 Introduction .......................................... 191
7.2 Relative Intensity .................................... 193
7.2.1 Multiplicity Factor ............................ 193
7.2.2 Electron and Atomic Scattering ................. 194
7.2.3 Structure Factor ............................... 196
7.2.4 Attenuation Factors ............................ 197
7.3 Geometry and Resolution ............................... 197
7.3.1 Detector Distance and Resolution ............... 198
7.3.2 Defocusing Effect .............................. 199
7.3.3 Transmission Mode Diffraction .................. 201
7.4 Sampling Statistics ................................... 202
7.4.1 Effective Sampling Volume ...................... 203
7.4.2 Angular Window ................................. 204
7.4.3 Virtual Oscillation ............................ 205
7.4.4 Sample Oscillation ............................. 206
7.5 Preferred Orientation Effect .......................... 208
7.5.1 Relative Intensity with Texture ................ 208
7.5.2 Intensity Correction on Fiber Texture .......... 211
References ................................................. 216
8 Texture Analysis ........................................... 218
8.1 Introduction .......................................... 218
8.2 Pole Density and Pole Figure .......................... 219
8.3 Fundamental Equations ................................. 222
8.3.1 Pole Figure Angles ............................. 222
8.3.2 Pole Density ................................... 224
8.4 Data Collection Strategy .............................. 225
8.4.1 Single Scan .................................... 225
8.4.2 Multiple Scan .................................. 227
8.4.3 Comparison with Point Detector ................. 230
8.5 Texture Data Process .................................. 231
8.5.1 20 Integration ................................. 231
8.5.2 Absorption Correction .......................... 234
8.5.3 Pole Figure Interpolation ...................... 235
8.5.4 Pole Figure Symmetry ........................... 235
8.5.5 Pole Figure Normalization ...................... 237
8.6 Orientation Distribution Function ..................... 237
8.6.1 Eulerian Angles and Space ...................... 237
8.6.2 ODF Calculation ................................ 239
8.6.3 Calculated Pole Figures From ODF ............... 241
8.7 Fiber Texture ......................................... 242
8.7.1 Pole Figures of Fiber Texture .................. 242
8.7.2 ODF of Fiber Texture ........................... 244
8.8 Other Advantages of XRD2 for Texture .................. 244
8.8.1 Orientation Relationship ....................... 245
8.8.2 Direct Observation of Texture .................. 245
References ................................................. 247
9 Stress Measurement ......................................... 249
9.1 Introduction .......................................... 249
9.1.1 Stress ......................................... 250
9.1.2 Strain ......................................... 254
9.1.3 Elasticity and Hooke's Law ..................... 256
9.1.4 X-Ray Elasticity Constants and Anisotropy
Factor ......................................... 257
9.1.5 Residual Stresses .............................. 258
9.2 Principle of X-Ray Stress Analysis .................... 260
9.2.1 Strain and Bragg Law ........................... 260
9.2.2 Strain Measurement ............................. 261
9.2.3 Stress Measurement ............................. 263
9.2.4 Stress Measurement Without d0 .................. 266
9.2.5 Ψ-Tilt and Goniometer .......................... 269
9.2.6 Sin2Ψ Method with Area Detector ................ 270
9.3 Theory of Stress Analysis with XRD2 ................... 272
9.3.1 2D Fundamental Equation for Stress
Measurement .................................... 272
9.3.2 Relationship Between Conventional Theory and
2D Theory ...................................... 276
9.3.3 2D Equations for Various Stress States ......... 278
9.3.4 True Stress-Free Lattice d-Spacing ............. 280
9.3.5 Diffraction Cone Distortion Simulation ......... 281
9.4 Process of Stress Measurement with XRD2 ............... 288
9.4.1 Instrument Requirements and Configurations ..... 288
9.4.2 Data Collection Strategy ....................... 291
9.4.3 Data Integration and Peak Evaluation ........... 295
9.4.4 Stress Calculation ............................. 299
9.4.5 Intensity Weighted Least Squares Regression .... 300
9.5 Experimental Examples ................................. 303
9.5.1 Comparison Between 2D Method and Conventional
Method ......................................... 303
9.5.2 Virtual Oscillation for Stress Measurement ..... 305
9.5.3 Stress Mapping on Weldment ..................... 307
9.5.4 Residual Stresses in Thin Films ................ 310
9.5.5 Residual Stress Measurement with Multiple
{hkl} Rings .................................... 315
9.5.6 Gage Repeatability and Reproducibility Study ... 316
Appendix 9.A Calculation of Principal Stresses from the
General Stress Tensor ........................ 320
Appendix 9.B Parameters for Stress Measurement ............ 323
References ................................................. 325
10 Small-Angle X-Ray Scattering ............................... 329
10.1 Introduction .......................................... 329
10.1.1 Principle of Small-Angle Scattering ............ 330
10.1.2 General Equation and Parameters in SAXS ........ 330
10.1.3 X-Ray Source and Optics for SAXS ............... 331
10.2 2D SAXS Systems ....................................... 333
10.2.1 SAXS Attachments ............................... 334
10.2.2 Dedicated SAXS System .......................... 336
10.2.3 Detector Correction and System Calibration ..... 337
10.2.4 Data Collection and Integration ................ 338
10.3 Application Examples .................................. 341
10.3.1 Particles in Solutions ......................... 341
10.3.2 Scanning SAXS and Transmission Measurement ..... 341
10.4 Some Innovations in 2D SAXS ........................... 343
10.4.1 Simultaneous Measurements of Transmission
and SAXS ....................................... 343
10.4.2 Vertical SAXS System ........................... 346
References ............................................ 347
11 Combinatorial Screening .................................... 351
11.1 Introduction .......................................... 351
11.1.1 Combinatorial Chemistry ........................ 351
11.1.2 Combinatorial Screening ........................ 352
11.2 XRD2 Systems for Combinatorial Screening .............. 352
11.2.1 Combinatorial Screening in Reflection
Geometry ....................................... 353
11.2.2 Retractable Knife-Edge ......................... 356
11.2.3 Combinatorial Screening in Transmission
Geometry ....................................... 359
11.3 Combined Screening with XRD2 and Raman ................ 364
References ............................................ 366
12 Quantitative Analysis ...................................... 369
12.1 Percent Crystallinity ................................. 369
12.1.1 Introduction ................................... 369
12.1.2 Comparison of Conventional XRD and XRD2 ........ 370
12.1.3 Scatter Correction ............................. 371
12.1.4 Internal and External Methods .................. 373
12.1.5 Full Method .................................... 374
12.2 Crystal Size .......................................... 376
12.2.1 Introduction ................................... 376
12.2.2 Line Broadening for Crystallite Size ........... 377
12.2.3 γ-Profile Analysis for Crystallite Size ........ 380
12.3 Retained Austenite .................................... 387
References ............................................ 390
13 Innovation and Future Development .......................... 393
13.1 Introduction .......................................... 393
13.2 Scanning Line Detector for XRD2 ....................... 394
13.2.1 Working Principle .............................. 394
13.2.2 Advantages of Scanning Line Detector ........... 396
13.3 Three-Dimensional Detector ............................ 398
13.3.1 The Third Dimension of a Detector .............. 398
13.3.2 Geometry of Three-Dimensional Detector ......... 399
13.3.3 Three-Dimensional Detector and Reciprocal
Space .......................................... 401
13.4 Pixel Direct Diffraction Analysis ..................... 402
13.4.1 Concept ........................................ 402
13.4.2 Pixel Diffraction Vector and Pixel Count ....... 403
13.4.3 PDD Analysis in Phase-ID, Texture, and
Stress ......................................... 404
References ................................................. 406
Appendix A. Values of Commonly Used Parameters ................ 407
Appendix B. Symbols ........................................... 412
Index ......................................................... 419
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