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Microstructure void volume fraction is taken into account in finite element models developed for large strain elastoplastic problems. Void nucleation rate is related to matrix effective strain rate, void growth to material strain rate and associated elastoplastic potential available for porous material, void coalescence to matrix effective strain rate. The related radial return algorithm is described. Three types of computations are proposed: first, axisymmetric Q4 element traction are given as validation example; second, collar cylinder compression are computed as reference example; third, bulk forming are analysed as large strain specific example. Void volume fraction and hydrostatic stress are mainly discussed according to microvoids nucleation, growth and coalescence. Finally, the main interests of those computations are enhanced.

New contact boundary modelling is achieved with a basic set of 2 and 3 dimension contact primitives. Contact constraints are originally introduced in the variational equations and associated Newton—Raphson scheme via an external penalty formulation using primitive equations. Consequently, penalty part of external load vector and tangent stiffness matrices are developed for all contact primitives. In this way, contact prescribed boundary displacements are also taken into account. Contact treatment is then completed with Newton—Raphson elements for elastic and plastic regularized friction constitutive models. In this paper, the process is extended to elastoplastic models. Finally, we propose a self acting procedure with contact algorithms (interiority, sliding and contact loss) and related subroutines for implementation in finite element framework. We illustrate these developments by means of two‐dimensional open die forging and three‐dimensional plate coining typical benchmarks with reference to bulk elastoplastic and viscoplastic constitutive models.

The place of G. H. Mead’s works in symbolic interactionism is both central and paradoxical. It stands at the very foundation of Hebert Blumer’s initial invention of symbolic interactionism with respect to Mead’s social behaviorism and has been discussed and debated ever since because of the problems caused by such a presumed direct filiation. Returning to Mead in order to broaden the perspective offered by Blumer is a must and has to face some fundamental issues raised in this context. This article starts by examining the ontogenetic and phylogenetic processes involved in Mead’s concept of society, in order to show the multiple dimensions involved in significant symbols. An illustration of Mead’s wider perspective is given in reference to the feminist movement as analyzed first by Mead’s student, Jessie Taft, and goes back to the origin of the movement with Mary Wollstonecraft. This leads to the analysis of the debate about the place of power in symbolic interactionism, initiated by Peter M. Hall, and addresses the alternative between domination and emancipation. This alternative has been worked out by Lonnie Athen’s radical symbolic interactionism analysis of domination on the one side, and by Kathy Charmaz and Norman K. Denzin on the other side of emancipatory symbolic interactionist practices. Another solution is proposed to this alternative, with the analysis of power being intrinsically constituted by domination and emancipation, in their respective contribution to the understanding of the symbolic dispositions of autonomy – a concept that remains relatively undeveloped in Mead’s works.

This chapter critically discusses the many positive aspects that are ascribed to gazelle firms by exploring the external effects and dark sides of high firm growth. On the background of the more general debate on purpose versus profit as a firm’s mission, the chapter theoretically elaborates on the dichotomy between quantitative and qualitative growth of gazelles. This is followed by a case-based illustration and exploration as to how quantitative and qualitative growth interrelates in gazelles and what are impediments for high growth that is purpose driven. The chapter closes with a discussion of the Janus-faced nature of gazelles and how their corporate citizenship can be enhanced.

Inside the finite element framework of LAGAMINE code, the contact conditions are introduced with specific two‐node interface elements and four‐node quadrangular elements or four‐node one point quadrature elements. A non‐associated flow rule is involved for sliding unilateral contact modelling. Two methods of penalty factor computations in the penalty contact algorithms are presented. These methods are then used for contact modelling of two isothermal examples: axisymmetric tube expansion and asymmetric slab bending, the material bulk constitutive equation being isotropic and elasto‐plastic.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming and powder metallurgy are briefly discussed. The range of applications of finite elements on the subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for the last five years, and more than 1100 references are listed.

Nowadays, simplified inverse or one step approaches for the sheet forming modeling are increasingly used in the automobile industry, since they allow to quickly realize the preliminary design and especially to optimize the process parameters. These methods often based on implicit static algorithms cause sometimes convergence problems because of strong non‐linearities. This paper deals with several initial guess methods to speed up the convergence of the implicit static solver used in the inverse approach for stamping modeling. The blank's mesh as initial solution is obtained by geometrical considerations based on the known shape of the final 3D workpiece. Three algorithms for the estimation of the blank's mesh have been developed and compared. The application to several industrial problems shows their efficiency and performance.