An experimental framework for determining wear in porous journal bearings operated in the mixed lubrication regime

We present an experimental and analysis workflow to characterize the tribological behavior and the wear resistance of porous journal bearing systems operating at high loads and small rotational speeds. Our approach consists of a laser-instrumented tribometer that allows parallel testing of five bearings, an experimental procedure that is optimized for producing sufficient wear during mixed lubrication operation while maintaining realistic operating conditions, as well as several methods to visualize and quantify bearing wear. The simultaneous testing of five bearings prevents outliers from distorting the results and yields a statistical estimation of the performance variations between nominally equivalent tribosystems. We showcase our approach by analyzing the influence of the bearing material and its porosity on mixed-lubrication friction and wear.