Effect of Mechanical Properties on Cavitation Erosion Resistance in γ → α ′ Phase Transformable Fe–Cr–C–Mn Alloys

The effect of mechanical properties on cavitation erosion resistance was investigated for γ → α′ phase transformable Fe–Cr–C–5Mn alloys. When comparing Fe–8Cr–0.7C–5Mn to Fe–16Cr–0.7C–5Mn, the volume fraction of transformed α′-martensite decreased with increasing Cr due to the decrement of the stacking fault energy. In previous study, cavitation erosion resistance increased with increasing volume fraction of transformed martensite. However, the cavitation erosion resistance was improved with increasing Cr. Although the volume fraction of transformed α′-martensite decreased with increasing Cr concentration, Cr addition caused increases in compressive strength and elongation. In the case of γ → α′ phase transformable alloys, it was considered that the strength and fracture strain are more important factors for determining the cavitation erosion resistance than the volume fraction of transformed α′-martensite.