Preface ..................................................... ix
1 Introduction ................................................. 1
1.1 Computational thermodynamics ............................ 1
1.2 The past and present, the Calphad technique ............. 3
1.3 The future development of databases and software
applications ............................................ 4
1.4 The structure of the book ............................... 5
2 Basis ........................................................ 7
2.1 Thermodynamics .......................................... 7
2.2 Crystallography ........................................ 17
2.3 Equilibrium calculations ............................... 23
2.4 Optimization methods ................................... 42
2.5 Final remarks .......................................... 45
3 First principles and thermodynamic properties ............... 47
3.1 The density-functional theory (DFT) and its
approximations ......................................... 48
3.2 The DFT results at 0К .................................. 50
3.3 Going to higher temperatures, adding the statistics .... 53
3.4 Final remarks .......................................... 57
4 Experimental data used for the optimization ................. 58
4.1 Thermodynamic data ..................................... 58
4.2 Binary phase-diagram data .............................. 68
4.3 Ternary phase-diagram data ............................. 72
4.4 Multicomponent and other types of experimental data .... 75
4.5 X-ray and neutron diffraction .......................... 76
4.6 Mössbauer spectroscopy and perturbed angular-
correlation measurements ............................... 76
4.7 Final remarks .......................................... 76
5 Models for the Gibbs energy ................................. 79
5.1 The general form of the Gibbs-energy model ............. 80
5.2 Phases with fixed composition .......................... 81
5.3 Variables for composition dependence ................... 87
5.4 Modeling particular physical phenomena ................. 91
5.5 Models for the Gibbs energy of solutions ............... 94
5.6 Models for the excess Gibbs energy .................... 103
5.7 Modeling using additional constituents ................ 114
5.8 Modeling using sublattices ............................ 122
5.9 Models for liquids .................................... 146
5.10 Chemical reactions and thermodynamic models .......... 155
5.11 Final remarks ........................................ 157
6 Assessment methodology ..................................... 161
6.1 Starting the assessment ............................... 161
6.2 Modeling the Gibbs energy for each phase .............. 167
6.3 Determining adjustable parameters ..................... 192
6.4 Decisions to be made during the assessment ............ 195
6.5 Checking results of an optimization ................... 198
6.6 Publishing an assessed system ......................... 200
6.7 How the experts do assessment ......................... 200
7 Optimization tools ......................................... 203
7.1 Common features ....................................... 203
7.2 How to use BINGSS ..................................... 206
7.3 The PARROT module of Thermo-Calc ...................... 219
7.4 Final remarks ......................................... 240
8 Creating thermodynamic databases ........................... 243
8.1 Unary data ............................................ 244
8.2 Model compatibility ................................... 244
8.3 Experimental databases ................................ 245
8.4 Naming of phases ...................................... 246
8.5 From assessments to databases ......................... 249
8.6 Database management and updating ...................... 252
8.7 Existing thermodynamic databases ...................... 253
8.8 Mobility databases .................................... 253
8.9 Nano-materials ........................................ 254
8.10 Examples using databases .............................. 256
9 Case studies .............................................. 264
9.1 A complete assessment of the Cu-Mg system ............. 264
9.2 Checking metastable diagrams: the Ag-Al system ........ 274
9.3 The Re-W a phase refit using first-principles data .... 276
9.4 A complete binary system: Ca-Mg ....................... 279
9.5 Modeling the γ-γ' phases: the Al-Ni system ............ 285
9.6 Assessment of a ternary oxide system .................. 287
9.7 Some notes on a ternary assessment, the Cr-Fe-Ni
system ................................................ 293
Appendix - websites ........................................ 297
References ................................................. 299
Index ...................................................... 307
|
