Influence of Phosphorus on the Load Carrying Capacity under Boundary Lubrication Conditions of Copper-6 Tin

Abstract

Addition of 0.02% phosphorus to a Cu-6Sn alloy reduces the desorption temperature for paraffin oil, containing 0.2% fatty acid, by more than 60 C. This means that, in the pin and ring geometry, the load carrying capacity in the boundary lubrication regime is lowered by a factor of 2 or more. Desorption is controlled by the over-all surface temperature of the bronze, rather than by the local hot-spot temperature. The desorption temperature is not influenced by viscosity and sliding speed. At conditions below critical, wear is probably of the abrasive type and the wear rate is independent of speed.