Plastic Deformation Behavior of Pre-Heat-Treated High-Strength Steel for Application in Forging

Abstract

The plastic deformation behavior of ESW105 and SCM435 steels was examined by simulations and experiments. ESW105 is a special and pre-heat-treated steel characterized by high initial yield strength and negligible strain-hardening behavior. The flow stresses of the two steels for large strains were calculated from tensile tests with their associated material identification algorithm. Axial and lateral compression behaviors of cylindrical bars were tested and simulated, and the deformed shapes were compared to characterize the plastic deformation behavior of the two materials. A two-stages forward extrusion process of a cylindrical bar, which is a part of the ball-stud forging process, was also simulated to determine difference between the two steels. The findings showed significant differences in metal flow between ESW105 and SCM435, which caused differences 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 ESW105 is used without considering its plastic deformation behavior.