Abstract:

The superplastic die bulging process under constant pressure is simulated by using large deformation rigid visco plastic finite element method(FEM).The effects of material parameters,such as the strain rate sensitive index m ,the strain hardening index n ,and the normal anisotropy index R , on some aspects in the bulging process,which include the thickness distribution of the workpiece,the forming time,the effective strain field,and the deformation ability of the material,are analysed and discussed comprehensively.Corresponding experiments are performed on aluminum alloy LY12CZ and good agreement is found between the numerical and experimental results.

Key words: material parameters, super plasticity, die-bulging under constant pressure, rigid visco-plastic FEM