Assessment of the Cavitation Resistance of Stainless Steel X5crni18-10, Subjected to Thermal Sensitization Based on Average Durability

Among the uses of stainless steel GX5CrNi18-10 one mentions the hydraulic machine blades and the rotors, which are highly susceptible to cavitation. To achieve a long life service under cavitation conditions, the pieces made of this steel are subjected to volumetric thermal treatments, which change the structure and mechanical properties. In this paper, one presents the results of the research concerning the behavior and the resistance to the cavitation erosion of the thermally sensitized GX5CrNi18-10 stainless steel, applying four different temperature regimes (two at 650°C and two at 750°C) and different durations (30 minutes and respectively 60 minutes). The results are presented in the form of cumulative mass loss curves M (t) and erosion rate v (t). The assessment of the cavitation resistance provided by each heat treatment regime is based on the average durability cavitation parameter, as defined by K. Steller. The research was conducted on the standard vibrator with piezo-ceramic crystals from the Cavitation Laboratory of the Politechnica University of Timisoara.