Explicit analysis of superplastic forming by the FEM including a pressure cycle control algorithm

In this paper, the results obtained by 3-D shell elements numerical simulation of superplastic sheet forming is compared with the experimental ones to verify the validity of the finite element model developed to predict the optimum pressure cycle, the deformed shapes, the distributions of the strain rate and the evolution of the thickness during the forming process. The finite element shell material model proposed here, includes membrane, bending and out-of-plane shear effects leading to a better characterisation of the material behaviour under forming conditions. Final results of the FEM modelling agree with the experimental ones.