Prediction of Tribological Limits in Sliding Contacts: Flash Temperature Calculations in Sliding Contacts and Material Behavior

Abstract

In order to achieve greater efficiency or to meet light weight requirements, components are downsized. This, however, increases the load, e.g., Hertzian or nominal contact pressures and stresses of tribosystems. This load is expressed as pa·v-value, the product of nominal contact pressure and sliding velocity. pa·v-values are an effective tool for design engineers for predicting low wear/high wear transitions. Therefore, in the present work, topographical analysis has been combined with the plasticity of micro-asperities and the flash temperatures to estimate the limits of pa·v diagrams. The central piece of this set of models presented here is the calculations for flash temperatures and contact mechanics of micro-asperities. This central piece is used to predict the performance of materials in high velocity (turbines, machinery) and low velocity (human joint) applications. It is shown that the model combination suggested here is a useful tool for screening and preselecting a candidate and new materials with respect to tribological requirements before engaging in expensive testing.