Thermal Analysis of Welds

Abstract

11R7. Thermal Analysis of Welds. - N. Nguyen. WIT Press, Southampton UK. 2004. 334 pp. ISBN 1-85312-951-8. $198.00. Reviewed by C A Rossit (Dept of Eng, Inst of Appl Mech and CONICET, 8000 Bahia Blanca, Argentina).This is a well-written book, which possesses an outstanding organization and clear and didactic figures. The book provides a very complete, up-to-date coverage of known solutions to an important variety of thermal problems related to welding processes. In the reviewer’s opinion the author synthesizes analytical expressions useful for the subject but with such a degree of abbreviation that it is not possible to follow the derivation of the expressions unless one is an expert on the subject. It would have helped if specific references were provided for each formulation. Chapter 1 introduces the characteristics of different heat sources associated with the welding process. Chapter 2 deals with the method of analysis for solving heat conduction differential equation. In Eq. (2.11) page 43 of this chapter one reads “∂2T∂x2+∂2T∂y2+∂2T∂z2=1α∂T∂t+fx,y,z,twhere fx,y,z,t represents the additional heat-generation function in the body…” and it is not clear the reason why the author places fx,y,z,t with positive sign on the right-hand side member, since this is not usual in the classical texts of the subject matter. On the other hand, the additional heat-generation must be divided by “k” in order to be compatible with the rest of the equation. After he divides it by “k” he could call it f1x,y,z,t for instance. Chapters 3 to 7 are concerned with the derivation of the analytical solution for different kinds of heat sources in semi-infinite and infinite bodies, thin and thick plates, and cylinders and spheres. Thus the author deals first with point, line, plane heat sources, and then by superposition principle analysis the bivariate Gaussian heat sources. Finally he focuses on the situations of spherical, single and double ellipsoidal density heat sources. Chapters 8 to 11 are addressed to demonstrate the usefulness of analytical solutions in solving thermal problems of welded components: transient temperature distribution, thermal stresses, residual stresses, and microstructures. The book contains three appendixes related to thermal properties of selected materials, error function characteristics, and documentation for Fortran programs developed by the author, respectively. The book also provides a CD-Rom, with a package called WHEATSIM, which is useful for the researcher in order to simulate welding situations. From a conceptual viewpoint it would have been interesting a short discussion, at least, of the possible importance of coupled thermal-mechanical phenomena and also dynamic effects in the case of very thin structures.