Microstructure and tribological behavior of a peak aged Cu–Cr–Zr alloy

The friction and wear behavior of peak aged Cu–Cr–Zr alloys dry sliding against a brass counterface were investigated on a pin-on-disk wear tester. The microstructure of the aged Cu–Cr–Zr alloy before and after wear tests was analyzed by transmission electron microscopy. The worn surfaces of the Cu–Cr–Zr alloys were studied by scanning electron microscopy and energy dispersive X-ray spectroscopy. The results indicated that an appropriate aging treatment resulted in the formation of fine, dispersive and coherent precipitates in the Cu matrix and thus could improve the hardness and wear resistance of the Cu–Cr–Zr alloy. The wear rate of the aged Cu–Cr–Zr alloy increased monotonically with increase of the normal load. With increasing sliding speed, the wear rate of the peak aged Cu–Cr–Zr alloy decreased initially and then began to increase. After reaching the maximum wear rate at a speed of 0.445 m s−1, the wear rate decreased again with further increasing in the sliding speed. Adhesive wear and abrasive wear were the dominant wear mechanisms under unlubricated conditions.