Over the last decade or so, additive manufacturing has revolutionized design and manufacturing methods by allowing more freedom in design and functionalities unattainable with conventional processes. This has generated extraordinarily high interest in both industrial and academic communities.
Additive Manufacturing of Metal Alloys 1 puts forward a state of the art of additive manufacturing and its different processes, from metallic raw materials (in the form of powder or wire) to their properties after elaboration. It analyzes the physics and the modelling of existing AM processes as well as future elaboration processes.
Using a balanced approach encapsulating basic notions and more advanced aspects for each theme, this book acts as a metal additive manufacturing textbook, as useful to professionals in the field as to the general public.
Table of Contents
Introduction ix
Patrice Peyre and Éric Charkaluk
Chapter 1 Metal Additive Manufacturing Processes 1
Patrice Peyre
1.1 The DED-LMD process 3
1.1.1 Process overview 3
1.1.2 Basic elements 4
1.1.3 Overview of process parameters and their influence 8
1.1.4 Thermal cycles induced by the process 13
1.1.5 Types of materials involved 15
1.1.6 Microstructures of manufactured or repaired parts 15
1.1.7 Industrial systems 16
1.2 The L-PBF process 21
1.2.1 Distinction between sintering and laser melting 21
1.2.2 Manufacturer interests and requirements 21
1.2.3 Process principle and basic elements 24
1.2.4 Types of materials involved 27
1.2.5 Presentation and influence of the process operating parameters 28
1.2.6 Comparison of the L-PBF process and DED process 31
1.2.7 Design and manufacturing method of a part 32
1.2.8 Area of stable melt-pool suitable for construction 37
1.2.9 Optimization of L-PBF manufacturing of 3D parts 38
1.3 Electron powder bed fusion 39
1.3.1 Introduction 39
1.3.2 Implementation of the E-PBF process 40
1.3.3 Optimization of melting conditions and characteristic defects 47
1.3.4 Other characteristics of the E-PBF process 52
1.3.5 Partial conclusion regarding E-PBF 57
1.4 The deposition of matter via WAAM 58
1.4.1 Arc/wire additive manufacturing technologies 58
1.4.2 WAAM process parameters 62
1.4.3 Use of materials 64
1.4.4 Residual stresses and distortions 67
1.4.5 Finishing process 68
1.4.6 Digital chain: online control 69
1.4.7 Conclusion 72
1.5 Emerging processes 72
1.5.1 Indirect fabrication by selective laser sintering and infiltration 72
1.5.2 Indirect manufacture via metal binder jetting 78
1.5.3 Direct manufacture in the solid state without melting 81
1.6 Conclusion 87
1.7 References 89
Chapter 2 Raw Materials: Metal Powders and Wires 97
Marc Thomas
2.1 Metal powders 97
2.1.1 Introduction 97
2.1.2 Producing powders 99
2.1.3 Physico-chemical properties of powders 115
2.1.4 Rheological properties of powders 117
2.1.5 Influence of powders on processes and final properties 125
2.1.6 Standardization 128
2.1.7 Summary 129
2.2 Metal wires 130
2.2.1 Introduction 130
2.2.2 Wire production 132
2.2.3 Use of filler wires in AM 135
2.2.4 Influence of wires on processes and final properties 137
2.2.5 Summary 146
2.3 References 147
Chapter 3 The Physics of Metal Additive Manufacturing Processes 151
Patrice Peyre
3.1 The energy-powder-fusion zone interaction in additive laser fusion processes 151
3.1.1 Introduction 151
3.1.2 Reminder of the essential physical variables 152
3.1.3 Radiation absorption and heat transfer: different interaction regimes for different processes 153
3.1.4 Local thermal cycles: influence of boundary conditions 163
3.1.5 Hydrodynamics of fusion zones and associated faults 164
3.1.6 Partial conclusion regarding the physics of laser additive manufacturing processes 171
3.2 The physics of the E-PBF process 171
3.2.1 Introduction 171
3.2.2 Reminder of the essential physical variables characteristic of the electron-matter interaction 171
3.2.3 The phenomena induced during the electron-matter interaction 173
3.2.4 Energy absorption in the powder in E-PBF 177
3.2.5 Description of the fusion zone in E-PBF and associated defects 180
3.2.6 Partial conclusion regarding E-PBF 183
3.3 Physics of the wire arc additive manufacturing process 183
3.3.1 Reminder of the essential physical variables 184
3.3.2 Arc-wire-deposit interaction 186
3.3.3 Form of deposits and associated defects 193
3.4 Conclusion 196
3.5 References 196
Chapter 4 Numerical Simulation of Additive Manufacturing Processes 201
Muriel Carin
4.1 Thermo-hydrodynamic simulation 201
4.1.1 Description of physical phenomena 201
4.1.2 Modeling of heat source 203
4.1.3 Modeling of material input 206
4.1.4 Numerical methods for deposition modeling 208
4.1.5 Modeling of heat and mass transfer in the melt-pool 210
4.1.6 Examples of thermo-hydrodynamic simulations 213
4.2 Thermomechanical simulation 221
4.2.1 Whole-part simulation: different techniques 223
4.2.2 Heat transfer resolution 224
4.2.3 Metallurgical resolution 225
4.2.4 Mechanical resolution 230
4.2.5 Coupling 232
4.2.6 Application at the mesoscopic scale: local manufacturing stresses 233
4.2.7 Application at the macroscopic scale 234
4.2.8 Software and calculation codes dedicated to additive manufacturing 238
4.3 Conclusion 238
4.4 References 239
Conclusion 243
Patrice Peyre and Éric Charkaluk
Abbreviations 245
List of Authors 255
Index 259
