J. Phys. IV France 08 (1998) Pr8-357-Pr8-364
Finite deformation Cosserat-type modelling of dissipative solids and its application to crystal plasticityR. Sievert1, S. Forest2 and R. Trostel3
1 Bundesanstalt für Materialforschung und -prüfung (BAM), Unter den Eichen 87, 12200 Berlin, Germany
2 École des Mines de Paris, Centre des Matériaux, UMR 7633 du CNRS, BP. 87, 91003 Evry, France
3 Techn. Univ. Berlin, Inst. für Mechanik (FB 10), 10623 Berlin, Germany
Recently, several proposals were made for the enlargement of the classical field equations in order to solve locally inhomogeneous deformation problems (e.g. at shear banding and damage localization or of composites). In the present paper basic issues of this topic will be treated : i) the implicit dependence within the gradient plasticity theory, ii) the more open micromorphic view-point of the gradient of internal variable approach, iii) a derivation of an elastic-plastic decomposition of the Cosserat strain measures, iv) its application to the description of lattice curvature in crystals. Finally, finite element simulations of strain localization in Cosserat single crystals are presented.
© EDP Sciences 1998