Residual stress evolution and surface morphology in grinding of hardened steel following carburizing and quenching processes

Abstract

AbstractIn this paper, the residual stress evolution and surface morphology of quenched 20Cr2Ni4A steel after surface grinding with alumina grinding wheel was investigated. The initial compressive residual stress in the surface layer evolved into tensile stress after grinding. Since thermal stress was the dominated factor, the effect of grinding speed and grinding depth showed significant effects on the level of residual stress. The tensile stress on the ground surface increased by more than 50 % when grinding speed increased from 26 m/s to 34 m/s at the feed speed of 0.19 m/s to 0.26 m/s. The increase of grinding depth from 0.02 mm to 0.03 mm resulted in the increase rate of tensile stress varying between 54 % and 85 % at specific feed speed and grinding speed. Due to the extrusion and cutting of abrasive particles, plastic deformation and grooves were found on the machined surface. The influence of grinding heat and grinding force caused a plastic deformation layer and grinding burn layer within 20 μm.