SLIDING WEAR OF CERAMIC METAL PAIRS UNDER BOUNDARY LUBRICATION OF WATER AND OIL/

In order to reveal the wear mechanism of ceramic cutting tools in real cutting process, a simulation test was carried out on a block-on-ring tribometer. The investigation was conducted at ambient temperature to determine the wear behaviour of ceramic/metal tribe-systems under bou ndary lubrication of water and oil. In this test, the boundary lubrica tion conditions were provided by dropping oil or water into contact ar ea at a rate of 5 drops per minute (about 0.1 ml/min). The tested mate rials are Al2O3-Ti(CN) composite ceramic, Al(purity>99.5 wt pet), Fe(C <0.04 wt pet) and a stainless steel (ASTM 302), which combined into th ree ceramic/metal frictional pairs. The test results indicate that wea r loss of the materials increases with load and speed. Compared with u nlubricated conditions, the boundary lubrication condition made the ma terials wear more serious, which show that lubricating method is very important to a tribe system, and unsuitable lubricating method could i ncrease the wear of materials instead of reducing it. The surfaces of the ceramic and the metallic samples were analysed by using a scanning electron microscope with energy-dispersive X-ray attachment, which in dicate that material transfer occurred between the ceramic and metalli c materials. The wear mechanism was discussed.