Boundary Lubrication of Undulated Metal Surfaces at Elevated Temperatures

Abstract

In the boundary lubricated sliding of metals, lubricant molecules desorb from metal surfaces as the interfacial temperature exceeds the transition temperature. As a consequence, numerous metallic contacts will be established, leading to adhesion and wear particle formation. The wear particles so formed plow the sliding surfaces, resulting in high friction and severe wear. In this paper, it is shown that friction can be reduced at elevated temperatures even with additive-free lubricants by using undulated surfaces. Flat and undulated OFHC copper surfaces were tested with various lubricants at different temperatures. Experimental results and theoretical analysis show that undulated surfaces minimize the plowing component of friction due to wear debris, thereby keeping the friction coefficient at a low value after the transition. Presented at the 43rd Annual Meeting in Cleveland, Ohio May 9–12, 1988