Study on Mechanical Properties of Cu-Bi Bearing Materials

Abstract

Cu-matrix bearing materials were prepared by powder metallurgy method and their mechanical properties were studied in present work. The continuity of copper alloy matrix was destroyed with the increase of Bi element. Because Bi is brittle phase and distributed in the copper alloy matrix grain boundaries as thin ribbon network. The hardness, crushing strength and impact toughness of copper-bearing materials were reduced with increase of the content of Bi. The mainly of Copper-bearing materials containing bismuth fracture are brittle intergranular fracture. When the Bi content is over 4wt%, the Bi has a relatively full distribution in the rich Bi phase of copper alloy matrix grain boundary like a chip mesh belt. As the further increase of Bi, the reduced trends of the mechanical properties of Cu-matrix bearing materials containing bismuth are slow down. because the role of fragmented Copper alloy matrix will not significantly increase with further increase of Bi.