Combination of Standard and Inverse Methods to Characterise the Anisotropic Behaviour of Aluminium Sheets. Inverse Method for Mechanical Tests on Sheets
The anisotropic behaviour of aluminium magnesium sheets is investigated. First, Lankford coefficients are determined from classical tensile test measurements at room temperature. The flow stress is estimated from the load measurements and the anisotropic coefficients are identified using the random pattern recognition system Aramis. In addition, Nakazima deep drawing tests have been performed and analysed using an inverse analysis module. This model is based on an optimisation method coupled with the 3D finite element program Forge3. The anisotropic behaviour of the aluminium sheets is modelled using a Hill yield criterion. The inverse analysis allows to identify the flow stress coefficients. Strain measurements obtained with the image correlation system are then used to identify parameters for Hill criterion, which are compared to the Lankford coefficients determined from tensile tests.
Yvan CHASTEL, Vincent NALEWAJK, Romain FORESTIER, Jean-Paul NAUZIN, Elisabeth MASSONI
Inverse Methods, Anisotropy, Aluminium Sheet, Deep Drawing.