Preparation of high strength and electrical conductivity copper-chromium pseudobinary alloy by cold-rolling of a billet produced by laser additive manufacturing

Abstract

A new method to prepare large Cu–Cr alloy with both high strength and high conductivity has been developed. Cu–Cr billets are produced efficiently by laser additive manufacturing, and the microstructure of the alloy is changed by severe plastic deformation caused by large cold rolling ratio. The strength of the alloy can be significantly increased to 677 MPa by eliminating pores, introducing texture and refining grain. The deformation twins caused by plastic deformation processing make up for the plasticity loss caused by grain refinement. With the increase of density and the deformation of Cr particles, the electrical conductivity of the alloy is increased to 28.7 MS/m. Our findings not only deepen the understanding of laser additive manufacturing of highly reflective metals, but also provide a new idea for the preparation of high-strength and high-conductivity Cu alloy workpieces.