Heat Effects of Welding

Almost all welding technology depends upon the use of concentrated energy sources to fuse or soften the material locally at the joint, before such energy can be diffused or dispersed elsewhere. Although comprehensive treatments of transient heat flow as a controlling influence have been developed progressively and published over the past forty years, the task of uniting the results compactly within a textbook has become increasingly formidable. With the comparative scarcity of such works, welding engineers have been denied the full use of powerful design analysis tools. During the past decade Dr Radaj has prepared to fulfil this need, working from a rich experience as pioneer researcher and teacher, co-operator with Professor Argyris at Stuttgart University in developing the finite element method for stress analysis of aircraft and power plant structures, and more recently as expert consultant on these and automotive structures at Daimler Benz. His book appeared in 1988 in the German language, and this updated English language edition will significantly increase the availability of the work.

Autorentext
Dieter Radaj, promoviert und habilitiert an der TU Braunschweig, war in Industrie, Wissenschaft und Lehre in unterschiedlichen Funktionen tätig. Seine Publikationen zur Festigkeitslehre und Technischen Mechanik sind weltweit anerkannt. Radaj ist zudem Autor eines Buches zu den buddhistischen Denktraditionen. Er lebt in Stuttgart.

Klappentext

Welding is the most important method of joining componentsmade of metallic materials. Most welding processes involvethe melting of the surfaces to be joined followed bysubsequent cooling. Melting is achieved by local heat input,keeping heat diffusion into the component and heatdissipation into the surroundings as low as possible. Theeffects of local heating are summarized under the term"weldability", a property of the structure to be weldedinfluenced by design, material and manufacturing measures.In recent years, theoretical developments in thermodynamics,continuum mechanics and microstructural kinetics have made asystematic assessment of weldability possible. This includesthe weldability-related optimization of design, materialsand welding processes. The systematic approach based ontheory and mathematics is termed "weldability analysis".This book isbased on this systematic approach. It proceedsfrom the temperature field, treats residual stress anddistortion on that basis and ends with practitioners'measures to reduce the former. A preliminary chapterintroduces the field and a final chapter reviews thestrength effects of welding.

Inhalt
1 Introduction.- 1.1 Scope and structuring of contents.- 1.2 Weldability analysis.- 1.3 Residual stresses.- 1.4 Welding residual stresses.- 1.5 Welding residual stress fields.- 1.6 Type examples.- 1.7 Welding deformations.- 1.8 References to related books.- 1.9 Presentation aspects.- 2 Welding temperature fields.- 2.1 Fundamentals.- 2.2 Global temperature fields.- 2.3 Local heat effect on the fusion zone.- 2.4 Local heat effect on the base metal.- 2.5 Hydrogen diffusion.- 3 Welding residual stress and distortion.- 3.1 Fundamentals.- 3.2 Finite element models.- 3.3 Shrinkage force and stress source models.- 3.4 Overview of welding residual stresses.- 3.5 Welding distortion.- 3.6 Measuring methods for residual stress and distortion.- 4 Reduction of welding residual stresses and distortion.- 4.1 Necessities and kinds of measures.- 4.2 Design measures.- 4.3 Material measures.- 4.4 Manufacturing measures.- 5 Survey of strength effects of welding.- 5.1 Methodical and systematical points of view.- 5.2 Hot and cold cracks.- 5.3 Ductile fracture.- 5.4 Brittle fracture.- 5.5 Lamellar tearing type fracture.- 5.6 Creep fracture.- 5.7 Fatigue fracture.- 5.8 Geometrical instability.- 5.9 Corrosion and wear.- 5.10 Strength reduction during welding.