Rolling Contact Fatigue Behavior in Surface Nanostructured Steels

Abstract

Surface nanostructured S45C, Si+B added S45C (S45C(Si+B)) and SCM440H steels were prepared by surface nanostructured wearing (SNW) and subsequent induction heating and quenching (IHQ). The Vickers hardness values at the top surface of these steels were around Hv 8.5 GPa, and also the thicknesses of quenched surface layer (Hv 7 GPa) were around 800 μm. The rolling contact fatigue lives of these steels in a roller pitting test were longer than those of the S45C, S45C(Si+B) and SCM440H steels without the surface nanostructure prepared by only IHQ. This is because the degree of the softening during the roller pitting test was smaller in the SNW&IHQed steels comparison with the only IHQed steels.