The scientific work of Jean Mandel has been exceptionally rich in the area of the mechanics of solids; the subjects which he has treated have been extremely diverse, from the theory of plasticity, buckling, soil mechanics, visco-elasticity, the theory of reduced models, and thermo dynamics, to percolation in porous media. But throughout this com prehensive work Jean Mandel has always maintained his interest in forming connections between the properties of materials (strength, deformability, viscosity) and the properties of their basic constituents. What is sometimes referred to in materials science as the transition from the microscopic to the macroscopic has for him been a very constant direction of research, which he never ceased to encourage in the Laboratoire de Mecanique des Solides of which he was the director. It is known that in the plasticity of metals permanent deformations must be sought in intercrystalline slip and more generally in disloca tions and the various microstructural defects. Before deformation of polycrystals is tackled, it is necessary to understand the mechanisms which take place within the crystal: the different systems of slip which may be activated and also the elementary mechanisms of twinning. Jean Mandel has shown how to make the transition from the behaviour of the single crystal to that of the polycrystal and has given the relation ships between the overall permanent deformation of the polycrystal and the plastic deformation of the single crystal.

This book gives a unified presentation of the research performed in the field of multiscale modelling in sheet metal forming over the course of more than thirty years by the members of six teams from internationally acclaimed universities. The first chapter is devoted to the presentation of some recent phenomenological yield criteria (BBC 2005 and BBC 2008) developed at the CERTETA center from the Technical University of Cluj-Napoca. An overview on the crystallographic texture and plastic anisotropy is presented in Chapter 2. Chapter 3 is dedicated to multiscale modelling of plastic anisotropy. The authors describe a new hierarchical multi-scale framework that allows taking into account the evolution of plastic anisotropy during sheet forming processes. Chapter 4 is focused on modelling the evolution of voids in porous metals with applications to forming limit curves and ductile fracture. The chapter details the steps needed for the development of dissipation functions and Gurson-type models for non-quadratic anisotropic plasticity criteria like BBC 2005 and those based on linear transformations. Chapter 5 describes advanced models for the prediction of forming limit curves developed by the authors. Chapter 6 is devoted to anisotropic damage in elasto-plastic materials with structural defects. Finally, Chapter 7 deals with modelling of the Portevin-Le Chatelier (PLC) effect. This volume contains contributions from leading researchers from the Technical University of Cluj-Napoca, Romania, the Catholic University of Leuven, Belgium, Clausthal University of Technology, Germany, Amirkabir University of Technology, Iran, the University of Bucharest, Romania, and the Institute of Mathematics of the Romanian Academy, Romania. It will prove useful to postgraduate students, researchers and engineers who are interested in the mechanical modeling and numerical simulation of sheet metal forming processes.

After a brief introduction into crystal plasticity,the fun- damentals of crystallographic textures and plastic anisotro- py, a main topic of this book, are outlined. A large chapter is devoted to formability testing both for bulk metal and sheet metal forming. For the first time testing methods for plastic anisotropy of round bars and tubes are included. A profound survey is given of literature about yield criteria for anisotropic materials up to most recent developments and the calculation of forming limits of anisotropic sheet me- tal. Other chapters are concerned with properties of workpieces after metal forming as well as the fundamentals of the theory of plasticity and finite element simulation of metal forming processes. The book is completed by a collection of tables of international standards for formability testing and of flow curves of metals which are most commonly used in metal forming. It is addressed both to university and industrial readers.

Proceedings of the IUTAM Symposium held in Bochum, Germany, 25-29 August 1997

Present developments in materials science, mechanics and engineering, as well as the demands of modern technology, result in a new and growing interest in plasticity and in bordering domains of the mechanical behavior of materials. This growing interest is attested to by the success of both The International Journal of Plasticity, which after its inception rapidly became the leading journal for plasticity research, and the series ofInternational Symposia on Plasticity and Its Current Applications, which is now the premier international forum for plasticity research dissemination. The First International Symposium on Plasticity and Its Current Applications was conceived and organized by Professor Akhtar S. Khan, and was held at the University of Oklahoma (Norman, Oklahoma, USA) from July 30 to August 3, 1984. It was attended by over one hundred scientists from fifteen countries. "Plasticity '89: the Second International Symposium on Plasticity and Its Current Applications" was held at Mie University (Tsu, Japan) from July 31 to August 4, 1989; this symposium was co-chaired by Professors Khan and Tokuda. The main emphasis of this meeting was on dynamic plasticity and micromechanics, although it included other aspects of plasticity as well. It was attended by over two hundred researchers from twenty-three nations.

The book gives a comprehensive view of the present ability to take into account the microstructure and texture evolution in building up engineering models of the plastic behaviour of polycrystalline materials at large strains. It is designed for postgraduate students, research engineers and academics that are interested in using advanced models of the mechanical behaviour of polycrystalline materials.