S. Jahanmir, “Model for Estimating Wear Transition Loads in Ceramics,” Frontiers in Tribology, Proceedings of 6th International Tribology Conference, Austrib 2002, G. W. Stachowiak (Ed.), Vol. 1, pp 39-46 (2002), Perth, Australia.
The wear behavior of advanced ceramics (alumina, silicon nitride, and silcon carbide) changes as the load or the coefficient of friction is increased. This change is associated with a drastic increase in wear rate at a critical load that depends on the material and test conditions. This transition from mild to severe wear occurs through a microfracture process at the sliding contact. Contact mechanics is used to develop a simple model to determine whether contact failure occurs by a classical brittle processes (i.e., cone cracking) or a quasi plastic behavior (i.e., small microcracks distributed below the contact surface). The model provides estimates of the transition load within a factor of two of the experimentally obtained values and indicates that the brittle behavior dominates the observed mild to severe wear transition in the three ceramics evaluated in this study.