Finite element modeling of superplastic sheet metal forming for cavity sensitive materials

In this paper a constitutive equation for superplasticity, which is based on the microstructural mechanism of superplastic deformation taking into account the effects of deformation damage, is incorporated into the finite element method to simulate the superplastic forming process. The effects of strain rate sensitivity, cavity growth and imposed hydrostatic pressure on the strain limit are studied. The predicted results are validated through the comparison with the existing experimental data. It is found that the present model produces accurate results in all cases.