Microstructure evolution and properties of a Cu-Cr-Zr alloy with high strength and high conductivity

Effects on microstructure evolution, mechanical and electrical properties of a Cu-Cr-Zr-Ni-Si-Ti alloy via multistage rolling and aging were investigated in details. The results showed that the optimal comprehensive performance of tensile strength (649 MPa) and electrical conductivity (65.5 %IACS) was obtained by three-stage rolling and aging (primary 80% room-temperature rolling (RTR) and aging at 450 degrees C for 2 h + secondary 60%RTR and aging at 300 degrees C for 1 h + tertiary 50%RTR and at 150 degrees;C aging for 1 h). Through the microstructure characterization, it was found that the orientation relationship between the precipitates and Cu matrix was (001)Cu //(001)Cr //(001)Ni2Si, [011]Cu //[011]Cr //[010]Ni2Si in the investigated Cu-Cr-Zr-Ni-Si-Ti alloy. The increase of yield strength was primarily attributed to fine grain strengthening and precipitation strengthening, and secondly attributed to dislocation strengthening. This work will provide a guideline for the fabrication of high-performance copper alloys.

Automated summary

The study investigated the effects of multistage rolling and aging on a Cu-Cr-Zr-Ni-Si-Ti alloy, and found that the optimal comprehensive performance can be achieved through three-stage rolling and aging. The microstructure and various strengthening mechanisms play key roles in improving the mechanical and electrical properties of the alloy.