A model to predict scuffing failures of a ball-on-disk contact

This study aims at establishing the criterion for scuffing to occur. A point contact thermal elastohydrodynamic lubrication (EHL) model is combined with a heat transfer model to predict the friction coefficient, surface bulk temperature and surface local temperature distribution. An experimental program is conducted to generate ball-on-disk scuffing failures under different rolling and sliding speeds and normal loads. Simulating these experiments, the model predictions are shown to be in good agreement with the measured ones. The probability distributions of the instantaneous maximum surface temperature under different operating conditions are constructed and observed to be bell shaped normal distributions. It is found the distribution median can be used as the measure to establish the scuffing limit for a lubricant-material (steel) combination.

► A heat transfer model for the surface bulk temperature prediction. ► A point contact mixed EHL model to predict heat generation. ► Ball-on-disk scuffing experiments for validation of the model.