水分对铜基摩擦材料摩擦磨损性能的影响

Effect of Water on Tribological Characteristics of Copper Based Friction Materials

采用粉末冶金工艺制备了含二氧化硅和石墨的铜基粉末冶金摩擦材料,利用定速摩擦试验机,分别在摩擦速度为7.8~47.1 m/s的范围内,探讨了干、湿摩擦条件下材料摩擦磨损性能的变化情况.结果表明：摩擦表面第三体的状态与干、湿摩擦条件密切相关,并影响材料的摩擦磨损性能.摩擦速度低时,材料的干摩擦系数高于湿摩擦情况,原因在于水起到隔离和润滑作用;摩擦速度提高,干摩擦系数低于湿摩擦条件,这归因于水分对表面的冷却作用降低了基体高温软化程度.

To investigate the tribological characteristics of Cu-matrix friction materials under dry and wet friction conditions,Cu-graphite-SiO2 sintering materials were prepared through powder metallurgic technique.The investigation was conducted on a pin-on-disk tester in the speed range of 7.8～47.1 m/s.The results demonstrate that the formation of the third bodies during friction is closely related to dry and wet friction conditions and significantly affects the friction and wear performance of the materials.At low speed,the friction coefficient under dry condition is higher than that under wet condition due to separation and lubrication of water film.As the speed increases,the friction coefficient under dry condition is lower than that under wet condition,which is attributed to the reduced softening extent of matrix under high temperature by cooling water.