Cavitation erosion behaviour of commercial steel grades used in the design of fluid-machinery

Abstract

The erosion response under cavitation of different steel grades was assessed by studying the erosion rate, the volume removal, the roughness evolution and the accumulated strain energy. A 20 kHz ultrasonic transducer with a probe diameter of 5 mm and peak-to-peak amplitude of 50 μm was deployed in distilled water to induce damage on the surface of commercial chromium and carbon steel samples. After a relatively short incubation period, cavitation induced the formation of pits, cracks and craters whose features strongly depended on the hardness and composition of the tested steel. AISI 52100 cromium steel showed the best performance and, therefore, it could be a promising design candidate for replacing the existing fluid-machinery materials that operate within cavitating environments.