Sliding Wear Testing and Data Analysis Strategies for Advanced Engineering Ceramics

Thousands of wear tests are conducted each year on advanced engineering ceramics, and the number will undoubtedly continue to grow. Most of these tests are conducted to screen or evaluate ceramic-based materials for specific applications; a smaller number are ostensibly conducted for more basic research purposes. Significantly, even the more generic testing is often justified by identifying potential applications for the results of that work. Most wear test methodology is derived from wear tests developed for metals and alloys. Use of such traditional methods is often adequate, especially if the method was based on a close simulation of the intended application. Differences in response to environment, fracture, and fatigue-related factors embodied in wear testing ceramics may, however, require modifications in testing strategy and in interpreting the significance of the results. Long incubation times for catastrophic wear transitions in ceramics may make accelerated or short-term testing risky. This paper outlines a strategy for designing sliding wear tests for ceramic materials using several examples for polycrystalline ceramics and ceramic composites. It also describes one procedure in which wear transition diagram methodology, developed for lubricated metals, can be adapted for use with ceramics.