Wear behavior of a Zr-based bulk metallic glass and its composites

The wear behaviors of Zr52.5Cu17.9Al10Ni14.6Ti5 metallic glasses with different contents of crystalline phases were studied by using a pin-on-disc test. The results indicate that the friction coefficient of the metallic glass with a steel counterpart is in the range of 0.24-0.32. Both surface softening and crystallization occur on the surface of the metallic glass during wear, and the wear curve is not as stable as the crystalline materials due to the interaction of the two processes. The wear mechanism of the metallic glass may change with wear conditions and the crystallinity. The fully amorphous material shows an abrasive wear at a low load, then adhesive wear at a high load. Increasing the crystallinity results in more abrasive wear. The wear behaviors of the metallic glass and its crystalline composites do not follow the Archard's equation. Only a good combination of the hardness and the toughness can the metallic glass be wear resistant.