J. Cirne, R. Dormeval, et al.
J. Phys. IV France 134 (2006) 139-145
Modelling and simulation of dynamic anisotropic degradation of structures under adiabatic shear bandingP. Longère1, A. Dragon2, H. Trumel3 and X. Deprince4
1 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
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