A Simplified Diagram of Seizure Criteria for Lubricated Sliding Rough Surfaces

Abstract

This paper describes an attempt to include surface roughness effects in the conventional pressure-velocity (PV) map for lubricated sliding surfaces. The criteria proposed involve two different boundaries: a plasticity limit and a temperature limit. The first criterion is given by a certain normal load to the system at which the plastically deformed asperities start interacting with each other. The second is given by an operating condition at which the surface temperature reaches a prescribed value. The effect of fluid film formation is considered in calculating effective normal load for these two criteria. By employing an exponential roughness height distribution and a long bearing approximation in fluid film pressure prediction, the diagram can easily be modified or reproduced for the system having different surfaces and materials. The diagram was adopted to evaluate a steel/steel end-face friction test result. Reasonable agreement was found.