EURODYMAT 2006 - 8th International Conference on Mehanical and Physical Behaviour of Materials under Dynamic Loading
J. Cirne, R. Dormeval, et al.
J. Phys. IV France 134 (2006) 139-145
DOI: 10.1051/jp4:2006134022

Modelling and simulation of dynamic anisotropic degradation of structures under adiabatic shear banding

P. Longère¹, A. Dragon², H. Trumel³ and X. Deprince<sup>4

1</sup>  Laboratoire de Génie Mécanique et Matériaux, Université de Bretagne Sud, 56321 Lorient, France
²  Laboratoire de Mécanique et de Physique des Matériaux (UMR CNRS 6617), ENSMA, 86961 Futuroscope-Chasseneuil Cedex, France
³  CEA/DAM, Le Ripault, 37260 Monts, France
⁴  GIAT Industries, 18023 Bourges Cedex, France

Published online: 26 July 2006

Abstract
The present work deals with the three-dimensional modelling of the behaviour of structural metallic materials allowing for adiabatic shear banding (ASB) as a mode of dynamic failure precursor. The anisotropic deterioration induced in the material by the presence of the bands is described via the concept of a “super dislocation” (see [6-8]) in the context of large viscoplastic deformation. The model accounts for strain hardening, thermal softening, rate sensitivity and includes ASB-induced anisotropy and softening in the post-critical stage. The onset of dynamic plastic localization in the form of ASB is controlled by a energy release rate threshold obtained from a linear perturbation method based analysis. 3D numerical simulations of the dynamic shearing of a hat shape structure (HSS) have been performed employing the code LS-DYNA and compared with experimental observations. The confrontation between numerical and experimental results constitutes the primary objective of this paper.

© EDP Sciences 2006