Wear of ceramic and ceramic-metal composites in high-speed dry sliding over steel

The wear of zirconia-based ceramics and WC-based ceramic-metal composites in high-speed dry sliding over steel is examined. The pin-on-disk technique is used up to a sliding speed of 47 m/sec. It is shown that tribolayers with complex composition form over ceramic and metal-ceramic materials and cause nonmonotonic changes in wear and friction. At the first stage, wear changes from normal to extreme high-intensity one with increasing sliding speed. At the second stage, steady-state wear is observed for the metal-ceramic composite and the wear rate of the ceramic material decreases virtually to its initial level typical of low sliding speeds (0.1 m/sec). Practically wearless friction of ceramics is observed over this range of speeds.