Development of Cold Forging Processes of Precipitation Hardening Stainless Steels

Abstract

Precipitation hardening stainless steels is difficult to deform them by cold forging process because of the high hardness and low elongation. This report is a fundamental study of cold forging in precipitation hardening stainless steels. In the present study, the forward extrusion followed by backward extrusion was conducted in order to confirm the possibility of consecutive plural cold forging process. By the optimization of the dies configuration and shape with simulation prediction, the target forming with rectangular depression over cylindrical depression and rectangular projection on opposite side could be obtained. The microstructure and work hardening behavior were estimated by grain flow visualization and hardness distribution.