The aim of this work is to study the strain localization during the plastic deformation of sheets metals. This phenomenon is precursor for the fracture of drawing parts, thus its prediction using advanced behavior models is important in order to obtain safe final parts. Most often, an accurate prediction of localization during forming process requi...
Ce travail consiste à étudier par simulation le phénomène du retour élastique dans le procédé d’emboutissage des tôles métalliques. Un modèle phénoménologique d’élasto-plasticité, incluant deux modèles d’écrouissage combiné, a été implanté dans le code d’éléments finis ABAQUS/Standard, via la routine UMAT, suivant un schéma d’intégration implicite....
In this work, a new physically stabilized and locking-free formulation of the SHB8PS element is presented. This is a solid-shell element based on a purely 3D formulation. It has eight nodes as well as five integration points, all distributed along the “thickness” direction. Consequently, it can be used for the modeling of thin structures, while pro...
In this paper, we present the different elements of connection between users requirements and physical phenomena created during the use of products. We propose a structured methodology which goes from the analysis of the significant moments until the identification of the appreciation criteria of the user and design variables necessary to the produ...
In order to extend the application range of the so-called ‘‘grid method’’ to the micron cale and thus quantitatively characterize the micromechanical behavior of metallic alloys, we report in this paper on the optimization of microscopic 2D gratings with pitches ranging from 1 to 10 mm. After an overview of the state of the art on full-field kinema...
The development of a relevant constitutive model adapted to sheet metal forming simulations requires an accurate description of the most important sources of anisotropy, i.e. the slip processes, the intragranular substructure changes and the texture development. During plastic deformation of thin metallic sheets, strain-path changes often occur in ...
In this paper, an extended version of Biot's differential equation is considered in order to discuss the quasi-static stability of a response for a solid in the framework of generalized standard materials. The same equation also holds for gradient theories since the gradients of arbitrary order of the state variables and of their rates can be intro...
L'auteur Francisco CHINESTA faisait parti en 2007 du Laboratoire de Mécanique des Systèmes et des Procédés (LMSP). Depuis 2010, le LMSP a fusionné avec deux autres unités de recherche en un seul laboratoire intitulé PIMM (Procédés et Ingénierie en Mécanique et Matériaux). / This work focuses on the resolution of the Fokker-Planck equation that gove...
Deux modèles micromécaniques de comportement élastoplastique, développés en adoptant une formulation en transformations finies et couplés à une technique de transition d’échelle autocohérente, sont utilisés pour étudier l'évolution des surfaces de charge d'un acier ferritique polycristallin lors de changements de trajets de déformation. L'importanc...
In this study, the formulation of the SHB8PS solid-shell element is reviewed in order to eliminate some persistent membrane and shear locking phenomena. The resulting physically stabilized and locking-free finite element consists in a continuum mechanics shell element based on a purely three-dimensional formulation. In fact, this is a hexahedral el...
