Abstract：Two-stage heat treatment/deformation processing with solution/cold-rolling and aging/cold-rolling of Cu-Cr-Zr alloy prepared by SPS was carried out, the microstructure, mechanical properties and electrical conductivity of the alloy were investigated. The results show that the SPSed Cu-Cr-Zr alloy matrix structure with uniform composition and fine grains, as well as the multi-scale of nano and sub-micron and multi-structure second phase with uniform distribution on the matrix were obtained by solution treated at 980 ℃ for 50 min, cold-rolled at 30% deformation, aged at 450 C for 2 h and cold-rolled at 70% deformation. The interactions of precipitation strengthening of the multi-scale second phase and strain hardening improved the strength and conductivity of the Cu-Cr-Zr alloy, and its tensile strength and electrical conductivity were 625 MPa and 79%IACS respectively, which were 143% and 20% higher than that of SPSed alloy.
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2019, Vol. 24 
