Effect of multifunction cavitation on microstructure and plane bending fatigue properties of low-alloy steel

Abstract

Multifunction cavitation (MFC) has potential as an environmentally friendly surface-modification method. In the present study, the modified surface layer and the fatigue properties for MFC-processed low-alloy steel were investigated. When the processing time was longer than 2 min, the surface roughness increased and the surface potential decreased. The maximum compressive residual stress was induced after a processing time of 2 min, and decreased for longer processing times. Electron backscatter diffraction analysis of a cross section of a sample subjected to MFC for 30 min showed that the modified layer was thicker than that for samples processed for shorter times. The fatigue life at high cycle numbers increased for the specimens processed by MFC under the conditions corresponding to the greatest compressive residual stress. MFC processing was shown to be effective in improving the fatigue properties of steel, and therefore has potential as a next-generation surface-modification method.

Keywords

• Multifunction cavitation
• Residual stress
• Fatigue
• Surface modified layer