True Friction Power Intensity and Scuffing in Sliding Contacts

Abstract

Scuffing failure phenomenon in sliding lubricated contacts is studied experimentally in this work. Factors influencing the scuffing resistance of rough surfaces, including contact temperature, surface pitting, specific film thickness, and frictional heating, are investigated. A new criterion (the TFPI criterion) that takes into account the effect of oil in surface roughness valleys, microcontact characteristics, and the protective film formation mechanism is proposed to predict onset of scuffing failure. Good agreement is found between experimental scuffing data and predicted failure criterion. The results show that the modified TFPI value can be considered as a performance parameter that represents the scuffing failure resistance capacity and the effectiveness of the running-in process. A low modified TFPI value has a high scuffing resistance in lubricated systems.