Cyclic Wear Behavior Produced by Thermal, Metallurgical, and Chemical Action

Abstract

Continuous monitoring of the wear of α brass on steel reveals a cyclic pattern, obscured by conventional intermittent measurement. Under dry conditions, an adhesive type of wear (I) at low speeds and loads is followed by a second type (II) when the surface temperature is sufficient to cause local recrystallization, estimated at about 250°C. Prows are then formed and the wear rate is reduced. A reversion from II to I can occur when the prow fails, usually by a fracture process. If, however, the temperature generated at the surface is higher still, oxidation will occur, giving low friction, smooth sliding and very little wear (type III). The temperature consequently falls and type I wear is again initiated, as the oxide wears away but cannot be reformed. A fourth type of wear can also occur under the most severe conditions, when the whole contact region is softened and gross metallic transfer occurs. This rapidly leads to catastrophic failure.

Presented at the 32nd Annual Meeting in Montreal, Quebec, Canada, May 9–12, 1977

Notes

Presented at the 32nd Annual Meeting in Montreal, Quebec, Canada, May 9–12, 1977