Hardenability of ASSAB 760 Steel during Tempering for Punch Holder Applications

Abstract

The purpose of this research was to evaluate the hardenability of ASSAB 760 (equivalent to AISI 1045 and JIS S45C) steel subjected to the gas cementation, the quenching and the tempering processes. Gas cementation is a heat treatment surface process by means of carbon diffusing into steel. This process is carried out in a furnace in a fluidized bed by using media of liquid petroleum gas (LPG) and nitrogen gas at a temperature of 1203 K and various holding times of 7.2, 10.8 and 14.4 ks, respectively. The rapid quenching process is carried out in an oil media for 420 sec. In order to remove the tension in the specimen, the tempering process is carried out in a furnace at a low temperature of 473 K with holding time of 3.6 ks. The result shows that, the Vickers hardness values can be achieved from 568 to 584 HV. Therefore, it is confirmed that by using these processes, the hardening of ASSAB 760 steel can be carried out and the punch holder can be manufactured.