Effect of Shot Peening Treatment on Forging Die Life

The aim of this paper was to study the effects of die life through shot peening treatments on AISI H13 steel, and tests were performed to study the influential parameters of the shot peening process. To evaluate the effects of microstructure and the die life of AISI H13 steel after steel shot peening processes, we conducted and evaluated roughness tests, micro hardness and wear tests, and SEM microstructure inspections. The shot peening process was conducted under a pneumatic peening machine. Experimental results showed that 0.3 mm steel shots and 30 minutes at 451 kPa of shot peening treatment was optimum for AISI H13 steel for improving wear resistance and the die life of steel. It enhanced the surface hardness to HV 561 and extended ability of the limit wear resistance for AISI H13 steel. Dislocation microstructure emerged on the steel surface by shot peening. In particular, this technology has been successfully applied to forging die, and is able to improve and extend the die life of steel 2 to 3 times. [doi:10.2320/matertrans.MER2007622]