Karkhin Thermal Processes in Welding

1. Auflage 2019
ISBN: 978-981-13-5965-1
Verlag: Springer Singapore
Format: PDF
Kopierschutz: 1 - PDF Watermark

E-Book, Englisch, 492 Seiten, eBook

Reihe: Engineering Materials

This book describes and systemizes analytical and numerical solutions for a broad range of instantaneous and continuous, stationary and moving, concentrated and distributed, 1D, 2D and 3D heat sources in semi-infinite bodies, thick plane layers, thin plates and cylinders under various boundary conditions. The analytical solutions were mainly obtained by the superimposing principle for various parts of the proposed 1D, 2D and 3D heat sources and based on the assumption that only heat conduction plays a major role in the thermal analysis of welds. Other complex effects of heat transfer in weld phenomena are incorporated in the solutions by means of various geometrical and energetic parameters of the heat source. The book is divided into 13 chapters. Chapter 1 briefly reviews various welding processes and the energy characteristics of welding heat sources, while Chapter 2 covers the main thermophysical properties of the most commonly used alloys. Chapter 3 describes the physical fundamentals of heat conduction during welding, and Chapter 4 introduces several useful methods for solving the problem of heat conduction in welding. Chapters 5 and 6 focus on the derivation of analytical solutions for many types of heat sources in semi-infinite bodies, thick plane layers, thin plates and cylinders under various boundary conditions. The heat sources can be instantaneous or continuous, stationary or moving, concentrated or distributed (1D, 2D or 3D). In Chapter 7 the temperature field under programmed heat input (pulsed power sources and weaving sources) is analyzed. In turn, Chapters 8 and 9 cover the thermal cycle, melting and solidification of the base metal. Heating and melting of filler metal are considered in Chapter 10. Chapter 11 addresses the formulation and solution of inverse heat conduction problems using zero-, first- and second-order algorithms, while Chapter 12 focuses on applying the solutions developed here to the optimization of welding conditions. In addition, case studies confirm the usefulness and feasibility of the respective solutions. Lastly, Chapter 13 demonstrates the prediction of local microstructure and mechanical properties of welded joint metals, while taking into account their thermal cycle. The book is intended for all researches, welding engineers, mechanical design engineers, research engineers and postgraduate students who deal with problems such as microstructure modeling of welds, analysis of the mechanical properties of welded metals, weldability, residual stresses and distortions, optimization of welding and allied processes (prewelding heating, cladding, thermal cutting, additive technologies, etc.). It also offers a useful reference guide for software engineers who are interested in writing application software for simulating welding processes, microstructure modeling, residual stress analysis of welds, and for robotic-welding control systems. 

Victor A. KARKHIN is a Professor at the Department of Welding and Laser Technologies, Peter the Great St. Petersburg Polytechnic University, Russia as well as an Honorary Doctor of Lappeenranta University of Technology, Finland. Has published more than 300 research and educational papers on the theory of welding processes, strength of welded structures, theory of welding stresses and distortion, mathematical modeling and optimization of technological processes. Has been a lecturer at various universities in the USSR, Germany, Norway and Finland. He is a Commission member of the International Institute of Welding and the International Organization for Standardization. His article 'Inverse Modelling of Fusion Welding Processes' was awarded the Kenneth Easterling Best Paper Award by the International Institute of Welding.

Zielgruppe

Professional/practitioner

Autoren/Hrsg.

Karkhin, Victor A.

Inhaltsverzeichnis

1;Preface to the English Edition;7
2;Contents;10
3;Symbols;14
4;Abstract;18
5;1 Energy Characteristics of Welding Heat Sources;19
5.1;1.1 Requirements for Welding Heat Sources;19
5.2;1.2 Welding Arc;19
5.3;1.3 Plasma Arc;34
5.4;1.4 Electron Beam;36
5.5;1.5 Laser Beam;38
5.6;1.6 Gas Flame;39
5.7;1.7 Electroslag Pool;41
5.8;1.8 Resistance Spot Welding;44
5.9;1.9 Resistance Butt Welding;46
5.10;1.10 Flash Welding;47
5.11;1.11 Friction Welding;47
5.12;1.12 Friction Stir Welding;48
5.13;1.13 Magnetically Impelled Arc Welding;53
5.14;References;54
6;2 Thermophysical Properties of Metals;59
6.1;2.1 Overview;59
6.2;2.2 Properties of Steels;62
6.3;2.3 Properties of Aluminium Alloys;64
6.4;2.4 Properties of Titanium Alloys;67
6.5;2.5 Properties of Magnesium;68
6.6;2.6 Properties of Copper Alloys;69
6.7;2.7 Properties of Nickel;69
6.8;References;71
7;3 Physical Fundamentals of Heat Conduction During Welding;73
7.1;3.1 Principal Definitions;73
7.2;3.2 Fourier’s Law of Heat Conduction;75
7.3;3.3 Differential Equation for Heat Conduction;76
7.4;3.4 Boundary Conditions;82
7.5;3.5 Accounting for Variability of Thermal Properties;86
7.6;3.6 Accounting for the Latent Heat of Phase Transformations;88
7.7;3.7 Models for Heat Sources;89
7.8;3.8 Schematisation of Heated Bodies;97
7.9;References;98
8;4 Methods for Solving the Problems of Heat Conduction in Welding;101
8.1;4.1 Classification of Methods for Solving the Problems of Heat Conduction in Welding;101
8.2;4.2 Functional-Analytical Methods for Calculation of Thermal Processes in Welding;102
8.2.1;4.2.1 Source Method;102
8.2.2;4.2.2 Method of Separation of Variables;122
8.2.3;4.2.3 Method of Integral Transformations;127
8.3;4.3 Numerical Methods of Calculating Thermal Processes in Welding;131
8.3.1;4.3.1 Finite Difference Method;132
8.3.2;4.3.2 Finite Element Method;140
8.3.3;4.3.3 Boundary Element Method;163
8.4;References;170
9;5 Temperature Fields in Fusion Welding;174
9.1;5.1 Temperature Fields of Concentrated Sources;174
9.1.1;5.1.1 Instantaneous Concentrated Sources;174
9.1.2;5.1.2 Stationary Continuous Concentrated Sources;181
9.1.3;5.1.3 Moving Concentrated Sources;185
9.1.4;5.1.4 Rapidly Moving Concentrated Heat Sources;228
9.2;5.2 Temperature Fields of Distributed Sources;238
9.2.1;5.2.1 Instantaneous Distributed Sources;239
9.2.2;5.2.2 Stationary Continuous Distributed Sources;266
9.2.3;5.2.3 Moving Distributed Sources;273
9.2.4;5.2.4 Rapidly Moving Distributed Sources;308
9.3;References;316
10;6 Temperature Fields in Welding with Pressure;321
10.1;6.1 Resistance Spot Welding;321
10.2;6.2 Resistance Butt and Flash Welding;327
10.3;6.3 Friction Welding;332
10.4;6.4 Friction Stir Welding;333
10.5;6.5 Magnetically Impelled Arc Welding;335
10.6;References;337
11;7 Temperature Fields Under Programmed Heat Input;339
11.1;7.1 Overview;339
11.2;7.2 Temperature Fields of Pulsed Power Sources;341
11.2.1;7.2.1 Point Source on a Semi-infinite Body;343
11.2.2;7.2.2 Point Source in a Slab;351
11.2.3;7.2.3 Line Source in a Plate;353
11.2.4;7.2.4 Plane Source in a Rod;355
11.2.5;7.2.5 Distributed Pulsed Power Sources;357
11.3;7.3 Weaving Heat Sources;361
11.4;References;366
12;8 Thermal Cycles of Metal During Welding;369
12.1;8.1 General Information;369
12.2;8.2 Rapidly Moving Point Source on a Semi-infinite Body;370
12.3;8.3 Rapidly Moving Point Source on a Slab;372
12.4;8.4 Rapidly Moving Line Source in a Plate;374
12.5;8.5 Cooling Time;375
12.6;References;378
13;9 Melting and Solidification of Base Metal;379
13.1;9.1 Weld Pool Dimensions;379
13.2;9.2 Melting Efficiency of Heat Source;380
13.2.1;9.2.1 Rapidly Moving Point Source on a Semi-infinite Body;380
13.2.2;9.2.2 Rapidly Moving Line Source in a Plate;381
13.3;9.3 Solidification of Weld Pool;381
13.4;9.4 Effects of Latent Heat;388
13.5;References;393
14;10 Heating and Melting of Filler Metal;396
14.1;10.1 Heating and Melting of Covered Electrodes;396
14.2;10.2 Heating of Electrode Wire;397
14.3;10.3 Melting of Electrode Wire;400
14.4;10.4 Heating and Melting of Filler Wire;403
14.5;References;405
15;11 Inverse Heat Conduction Problems in Welding;406
15.1;11.1 Formulation of an Inverse Heat Conduction Problem;406
15.2;11.2 Solution of an Inverse Heat Conduction Problem;410
15.2.1;11.2.1 Zero-Order Method;412
15.2.2;11.2.2 First-Order Method;415
15.2.3;11.2.3 Second-Order Method;416
15.3;References;421
16;12 Optimisation of Welding Conditions;425
16.1;12.1 Optimum Heat Input in Girth Welding of Thin-Walled Small Diameter Pipes;425
16.2;12.2 Optimisation of Pulsed Power Welding Conditions;427
16.3;12.3 Optimisation of Strip Electrode Shape for Cladding;432
16.4;12.4 Optimisation of Welding Conditions with Restrictions for Peak Temperature;435
16.5;12.5 Optimisation of Plate Edge Preheating Conditions in Butt Welding;438
16.6;12.6 Minimisation of Transient and Residual Stresses;443
16.6.1;12.6.1 Optimisation of Local Heating Conditions During Welding to Prevent Hot Cracking;443
16.6.2;12.6.2 Minimisation of Longitudinal Residual Stresses Using Additional Local Heating During Welding;447
16.6.3;12.6.3 Optimisation of Welding Conditions for Obtaining Required Residual Stresses;449
16.7;References;452
17;13 Prediction of Local Microstructure and Mechanical Properties of Welded Joint Metal with Allowance for Its Thermal Cycle;455
17.1;13.1 Microstructural Zones of Welded Joint;455
17.2;13.2 Microstructure of Heat Affected Zone Metal in Single-Pass Welding;457
17.3;13.3 Microstructure of Heat Affected Zone Metal in Multi-Pass Welding;464
17.4;13.4 Mechanical Properties of Steels in the Heat Affected Zone and Weld;468
17.4.1;13.4.1 Mechanical Properties of Heat Affected Zone Metal;468
17.4.2;13.4.2 Mechanical Properties of Weld Metal;471
17.5;13.5 Microstructure and Mechanical Properties of Aluminium Alloys;473
17.6;13.6 Effect of Thermal Cycles on Mass Diffusion Processes in Welding;473
17.7;13.7 Optimisation of Inert Gas Tungsten Arc Welding Conditions for Stainless Steel;480
17.8;References;482
18;Index;485

Energy characteristics of welding heat sources.- Thermal properties of metals.- Physical fundamentals of heat transfer during welding.- Methods for solving problems of heat conduction in welding.- Temperature fields in fusion welding.- Temperature fields in pressure welding.- Temperature fields with a programmable input of heat.- Metal heat cycles during welding.- The melting and solidification of the base metal.- Heating and melting the filler metal.- Inverse heat conduction problem in welding.- Optimization of welding.- Microstructure and mechanical properties of the metal Prediction different zones weld thermal cycles in view.

Über Autor(innen)

Victor A. KARKHIN is a Professor at the Department of Welding and Laser Technologies, Peter the Great St. Petersburg Polytechnic University, Russia as well as an Honorary Doctor of Lappeenranta University of Technology, Finland. Has published more than 300 research and educational papers on the theory of welding processes, strength of welded structures, theory of welding stresses and distortion, mathematical modeling and optimization of technological processes. Has been a lecturer at various universities in the USSR, Germany, Norway and Finland. He is a Commission member of the International Institute of Welding and the International Organization for Standardization. His article “Inverse Modelling of Fusion Welding Processes” was awarded the Kenneth Easterling Best Paper Award by the International Institute of Welding.