As-cast, age-hardened Cu-Sn-Ni worm gearing and method of making same

摘要

Worm gearing having improved wear and strength properties comprises a Cu, 8.0-13.0 w/o Sn, 3.5-5.0 w/o Ni alloy aged in the as-cast condition to strengthen the dendritic microstructural constituent (e.g., alpha phase) while retaining the as-cast, relatively hard interdendritic constituents. The overall Ni concentration of the alloy does not exceed about 5 w/o and the Ni concentration across individual as-cast dendrites is decreased at the dendrite edges (grain boundaries) to hinder formation of a discontinuous, embrittling grain boundary product that is deleterious to these properties.