Improvement of Cavitation and Silt Erosion Resistance for Austenitic Steel and SiC Alloy Made by Plasma-transferred-arc Powder Welding Method

Metallography, hardness, cavitation erosion weight loss, and silt erosion weight loss were examined for austenitic steel and SiC powder prepared by the plasma welding method, SiC content powder varied from 0 to 15 wt%. The resistance was improved with an increase of SiC content. According to EDX analysis, Si, Ni, and Co were found in matrix and Cr, Mo, and Fe were found in precipitates. It is suggested that SiC is decomposed during melting and C forms new carbide with Cr, Mo, Fe. The reaction may cause the improvement of cavitation and silt erosion resistance.