Influence of carbide density on surface roughness and quasi-stable wear behaviour of H13 die steel

Influence of cryogenic treatment on AISI H13 hot work die steels has been studied to correlate carbide density with surface roughness and dry sliding wear. This work includes hardening of AISI H13 specimens at 1020 degrees C, oil quenching followed by double tempering at 500 degrees C and then cryogenic treatment at -185 degrees C for different cryosoaking periods from 8 to 32 h, followed by soft tempering at 100 degrees C. The dry sliding wear behaviour on pin-on-disc has been studied for a load of 40 N at a speed of 3 m s(-1) for the sliding distance of 6000 m. A model has been proposed to elaborate upon the effect of tertiary carbide precipitation on the improvement of surface roughness, followed by establishing quasi-stable wear mechanism and the interpretation obtained from the Avrami equation of kinetics. A logical correlation has been established between carbide density and surface roughness.