Analyzing pin-on-ball wear tests by means of the Greenwood–Williamson contact model

For the calculation of micro contact parameters of rough surfaces, there are some models available by which one can calculate the micro contact pressure and area. Some of them require large computers and long computing time. Still, all these models represent just one specific contact condition. In order to gain results, fast statistical micro-contact models can be used, if the contact conditions allow for it. In this study the outcome of boundary lubricated multidirectional pin-on-ball wear tests of polished and textured metal surfaces is analyzed by means of micro contact parameters according to the Greenwood–Williamson model. Thus, surface profiles are measured at different loading cycles during run-in and steady state up to 500,000 cycles. These profiles are evaluated statistically as to the main parameters, e.g. the zeroth, second, and fourth spectral moments representing the variance of the heights, slope, and curvature of the asperities. These and the plasticity index are discussed with respect to their possible relationship to wear behavior.