Modeling Steel Deformation in the Semi-Solid State (eBook)

Acknowledgment 6
Contents 7
Nomenclature 10
Abstract 13
1 Introduction 14
2 State of the Art 17
References 28
3 Aim of the Study 34
4 Integration of Physical and Computer Simulation 36
4.1 Characteristics of the Integrated Modelling Concept 36
4.2 Hybrid Analytical-Numerical Model of Mushy Steel Deformation 41
4.2.1 Resistance Heating Model 45
4.3 “One Decision Software”—The DEFFEM Package 46
4.4 Summary 49
References 50
5 Spatial Solutions Based on the Particle Method 51
5.1 Introduction 51
5.2 The Smoothed Particle Hydrodynamics (SPH) Method 53
5.2.1 Fluid Model 55
5.3 Test Cases to Validate the Solver 57
5.3.1 Free Particles Fall 57
5.3.2 Structure Impact 61
5.4 Summary 63
References 64
6 Spatial Solutions Based on the Finite Element Method 66
6.1 Thermal Model 66
6.1.1 Discretization for Steady Heat Flow Cases 71
6.1.2 Discretization for Transient Heat Flow Cases 72
6.2 Solidification Model (FEM Approach) 74
6.3 Mechanical Model 76
6.3.1 Spatial Solution 77
6.3.1.1 Transformation of the Coordinate System and Integration 83
6.3.1.2 Time Problem 88
6.4 Solidification Model (CAFE Approach) 90
References 92
7 Physical Simulation of Steel Deformation in the Semi-solid State 94
7.1 Material and Test Methodology 96
7.1.1 Samples and Tools 97
7.1.2 The Determination of Characteristic Temperatures 98
7.1.3 Thermal Process Map (TPM) 102
7.2 Preliminary Experimental Research of Steel Deformation in the Semi-solid State 103
7.2.1 The Dependence of Steel Microstructure Parameters on the Cooling Rate During Solidification 105
7.2.2 Steel Ductility Tests 110
7.2.3 Macrostructure and Microstructure 118
7.3 Summary 126
References 127
8 Modelling Concept Based upon Axially Symmetrical Models 129
8.1 Direct Simulation Using the Gleeble Thermo-Mechanical Simulator 129
8.1.1 Testing the Temperature Distribution 130
8.1.2 Macrostructure and Microstructure 133
8.2 Application of Tomography to the Spatial Analysis of the Melting Zone 141
8.3 Numerical Modelling with the DEFFEM Simulation System 148
8.3.1 Modelling of the Resistance Heating Process 148
8.3.1.1 Example Results of Resistance Heating 153
8.3.2 Modelling the Deformation Process 159
8.3.2.1 Rheological Model 160
8.3.2.2 The Numerical Identification Methodology (NIM) for the Low Temperature Range 162
8.3.2.3 The Direct Identification Methodology (DIM) for the Extra-High Temperature Range 165
8.3.2.4 The Numerical Identification Methodology (NIM) for the Extra-High Temperature Range 172
8.4 Summary 180
References 181
9 Modelling Concept Based upon Three-Dimensional Models 182
9.1 Modified Experimental Research Methodology 182
9.2 Resistance Heating Model 185
9.3 Modelling the Resistance Heating Process 187
9.4 Deformation Process 197
9.5 Microstructure 202
9.6 Summary 213
References 215
10 Summary and Future Work 216
Appendix A 219
Appendix B 223
Appendix C 228
Appendix D 240
Appendix E 243