Effects of supply of fine oxide particles onto rubbing steel surfaces on severe–mild wear transition and oxide film formation

This study is the first to show a quantitative condition required for the establishment of severe–mild wear transition with sliding distance, by studying the effects of supply of Fe2O3 particles onto rubbing steel surfaces on the transition and oxide film formation process. The supply of fine Fe2O3 particles was found to accelerate the wear transition, and the sliding distance at which the transition occurs was found to increase with particle diameter and applied load. Oxide films are produced on the rubbing surfaces by sintering of the supplied Fe2O3 oxide particles. At the severe–mild wear transition, the relative area of oxide films is the same for all diameters of supplied Fe2O3 particles. This finding suggests that the transition occurs when the relative area of oxide films reaches a specific value, which is proportional to the area of real contact.