Scuffing as Evaluated From the Viewpoint of Surface Roughness and Friction Energy

The surface scuffing occurring in line-contact lubrication is related to the roller's roughness pattern and asperity height. For surfaces with same contact asperity height, the magnitudes of friction power (P_f = fWV_s) relevant to various roughness patterns are found to have the same sequence as the critical local temperatures. Instead of using the nominal contact area, the real contact area (A_t) is used to obtain the true friction power intensity (P_tfi = P_f/A_t). A new scuffing failure model (P_tfi · σ^-0.317, where a denote rms roughness) shows that the scuffing resistance of surfaces with transverse roughness pattern is higher than that of surfaces with longitudinal and oblique patterns. For certain roughness patterns, a high root mean square roughness height σ is always associated with the high P_tfi is value just before scuffing.