Computer simulation of the deep extrusion of a thin-walled cup using the thermo-mechanically coupled elasto-plastic FEM

Abstract During bulk metal forming processes, the workpieces are usually subjected to extremely large deformation with change of temperature. In this paper, a thermo-mechanically coupled elasto-plastic FEM system has been developed based on ANSYS software and the finite strain theory. Using this system, the deep warm extrusion of a thin-walled cup has been simulated. The basic parameters for process development and die design such as the metal flow, and the distribution of stresses, strains and temperature in the die and the workpiece, taking into account conduction, convection, radiation and plastic work, the loading–time curve, and the cause of failure on the punch, are obtained and analyzed. Industrial experiments have been carried out. The computer simulation results are in good agreement with the experimental results.

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