Damage and rupture of anisotropic metals for the dynamic and the crash of vehicles

Abstract
The prediction of damage and crack propagation plays an increasingly important role in the design of current vehicles and espeeially for those to come, In order to accurately prediet the damge and failure evolution occurring in crash simulations, a realistic material description is required. The damage variable must consider the mierostruetural characteristics of the material. For this purpose, the shape and orientation of the microstructural cavities are taken into account in the developed finite element model so as to improve prediction of damage and fracture occurrence. The growth, nucleation and coalescence phases are considered to describe the evolution of the microvoid volume fraction. This model has been implemented into the finite element code, PAM-SOLID An identification procedure for the matenal parameters is developed using an inverse method. This procedure is based on the correlation between experimental measurements obtained from tensile tests and numerical simulations. The identification was carried out automatically by using an optimiser coupled with the finite element code for an anisotropie aluminium material obtained from an extruded tube member. The use of the damage model is illustrated by several bending of extruded notehless aluminium tubes and then with a notched aluminium tubes.