Influence of Ag micro-alloying on the microstructure and properties of Cu–7Cr in situ composite

Abstract

This paper studied the influence of Ag micro-alloying on the deformation-processed Cu–7Cr in situ composite, by a comparison of Cu–7Cr and Cu–7Cr–0.07Ag. For both alloys, the as-cast microstructure consisted of a Cu matrix and Cr dendrites; after hot and cold working the microstructure consisted of a Cu matrix containing Cr fibres elongated in the working direction. The as-cast microstructure of the Ag-containing alloy contained finer Cr dendrites. The Ag-containing in situ composite had thinner Cr fibres, higher tensile strength, higher ductility, and slightly higher conductivity. The Cu–7Cr–0.07Ag in situ composite had a good combination of properties: a tensile strength of 772 MPa and a conductivity of 77.3%IACS.