Tensile and thermal properties, and microstructural evolution of additive-manufactured CuCrZr alloy at elevated temperature

Laser additive manufactured (LAM-ed) copper alloys with post-heat-treatments own excellent thermal and mechanical properties at ambient temperature. Nevertheless, for high-heat-flux copper alloys, the lack of understanding on microstructural evolution and properties at elevated temperatures. Herein, thermal and tensile properties of LAM-ed copper-chromium-zirconium (CuCrZr) alloy at elevated temperatures were investigated. The remained tangled dislocations, dislocation walls, low stacking fault energies, irregular grain and subgrains, high-dense body-centered-cubic nanoscale Cr and Zr-rich particles, high fraction of high-angle grain boundaries, retarded partial recrystallization and then made the alloys maintain good tensile and thermal properties (tensile strength: 180 MPa, elongation: 6.1%, thermal conductivity: about 290 W·m -1 ·K -1 ) at 600 °C. The present work achieved the synthesis of high-strength and high-thermal conductive copper alloys at elevated temperatures, which can provide engineering applications for high-performance AM-ed metals when serving in extreme environment.