Effect of strain hardening capability on plastic deformation behaviors of material during metal forming

Abstract

A comparative study of a pre-heat-treated steel PHTS and the SCM435 steel is made by simulations and experiments. PHTS is characterized by high initial yield strength and negligible strain-hardening capability while SCM435 is a typical strain hardening material. Material identification is first conducted. To characterize the plastic deformation behaviors of the two materials, predictions of cone indentation are compared. Predictions and experiments of axial compression of cylindrical specimens are also compared. In addition, a forward extrusion process, a backward extrusion process, a heading process, a forward and backward extrusion process and a four-stage forging process are simulated to examine the difference between the two steels. The findings has shown significant differences in metal flow between PHTS and SCM435, which is due to the difference in strain-hardening capabilities, indicating that experience-oriented design rules for common commercial materials may lead to failures in process design if the new material PHTS is used without considering its plastic deformation behavior. (C) 2013 Elsevier Ltd. All rights reserved.