Microstructure and properties of a Cu-6Cr alloy with high friction and wear resistance

The microstructural evolution, electrical conductivity, and mechanical properties of a cast Cu-6Cr alloy were investigated after being homogenized at 900 °C for 4 h, hot-rolled by 80%, solid solution treated at 940 °C for 2 h, and subjected to two steps of cold rolling and aging treatment. After several thermomechanical processes (HR + SST + CR + AT + CR + AT), the microhardness (155.2 HV), yield strength (439.8 MPa), and ultimate tensile strength (473.7 MPa) are significantly improved, and maintained a good electrical conductivity of 87.0 %IACS. Furthermore, under a load of 50 N and speed of 200 r/min, the alloy demonstrates a good friction coefficient of 0.381 and a wear rate of 1.62 × 10−8 mm3/(N·m). The wear mechanisms of the experimental alloy were abrasive wear and oxidative wear under low loads and low speeds, and oxidative wear and adhesive wear under high loads and high speeds.