莫来石陶瓷的摩擦磨损特性

采用环-块式摩擦副,研究了自相配莫来石陶瓷在不同的介质和载荷下的摩擦磨损特性.试验结果显示,莫来石陶瓷以水为介质时在20N、以机油为介质时在1000N附近存在磨损突变.磨损突变前主要的磨损机理为塑性变形和犁耕;磨损突变后断裂磨损成为主要的磨损机理.机油为介质时,磨损率与载荷基本成线性关系;在以水为介质时,磨损突变前,这种关系更接近于0.40次幂.弹性模量和抗弯强度高、断裂韧性和硬度低的样品,其磨损率高.通过扫描电子显微镜形貌观察,发现在水为介质时,磨损表面被一层反应膜所覆盖.

The Properties of Friction and Wear of Mullite Ceramics

Wear tests were carried out on the different self-mated mullite ceramics in water and machine oil environment at different loads,using block-on-ring tribometer.The worn surfaces were analyzed using scanning electron microscopy technique.Experimental results showed that wear transition occurred under the load exceed 20 N in water lubrication and about 1000 N in machine oil.The main pre-transition wear mechanism was plastic deformation and ploughing,while fracture was the dominant of post-transition.The relationship between the wear rate and the load was linear for machine oil lubrication and 0.40 power for water.Samples that had higher elastic modules and bending strength and lower fracture toughness and hardness had higher wear rates.Reaction layers was found on the worn surfaces when water was the lubricant.