Improving Cavitation Wear Resistance of Cast Iron Valve Castings by Applying Austenitic Steel Overlays

This study presents the results of cavitation wear resistance tests of AISI 307 and AISI 316 steel overlays. The overlays were applied using plasma cladding. The cladding was performed on spheroidal graphite cast iron castings with a ferritic-pearlitic matrix. The cavitation wear process was analyzed based on surface topography measurements, focusing on the Sz parameter, defined as the height difference between the highest peak and the deepest valley on the surface. Additionally, surface condition after cavitation exposure was examined using scanning electron microscopy. The material currently used for valve components, i.e. cast iron, exhibits significantly lower cavitation resistance compared to the overlays made of AISI 307 and AISI 316 stainless steels. The application of plasma cladding to produce surface overlays significantly increases the service life of cast iron valve components exposed to hydraulic impact, particularly in environments where cavitation-induced degradation occurs.