Evaluation of Erosion-Resisting Properties of Plastics and Metals Using Cavitating Jet Apparatus

The cavitation erosion resistance of various plastics and metals was assessed using a cavitating jet apparatus. The results of this work showed that cavitation resistance increased in the following order: stellite > stainless steels (martensitic > precipitation hardening > austenitic) > polyetheretherketone (PEEK) > polytetrafluoroethylene (PTFE) > aluminum alloy (Al-Mg). The maximum erosion rates of specimens made of aluminum alloy and plastics occurred in an early stage of exposure. By contrast, the erosion rates of stainless steel and stellite increased only slightly. The specimen made of PEEK showed the highest erosion resistance among plastics. Using “modified resilience”, a newly proposed normalized erosion index, showed a good correlation with the erosion-resisting rates for both plastics and metals.