Fig. 5
From: The effect of QPQ treatment on the wear and corrosion resistance of 42CrMo bearing steel
The hardness gradient is distributed across the cross-section of specimens undergoing different QPQ treatment processes. (a) 580℃×90 min, (b) 580℃×120 min, (c) 620℃×90 min, (d) 620℃×120 min.
