Abstract:

In this paper, based on the plastic theory of porous metal materials, the deformation process of cylindrical upsetting of porous materials has been simulated by the compressible rigid plastic finite element method(FEM). Meanwhile, with the help of the local strain limit criterion obtained by Lee Kuhn′s experiments, the limit process parameters, which include the frictional coefficient (m) , the relative height (H/D) and the initial relative density( R 0 ), have been calculated for the cracking on surface. Compared with that of Lee Kuhn′s experiments, the calculated results show that the method proposed in this paper is not only applicable, but also reliable.

Key words: porous materials, forging, defect predictions