高速制动工况下Cu基粉末冶金闸片材料摩擦磨损性能

Tribological Performances of Cu-based Powder Metallurgy Brake Pads Under High-speed Braking Condition

采用粉末冶金工艺,制得铜基摩擦材料;利用MM-1000Ⅱ型摩擦磨损试验机模拟列车实际工况条件,测试其摩擦磨损性能;用扫描电镜观察铜基摩擦材料表面磨痕,并分析其磨损机制。结果表明：一定制动压力下,铜基摩擦材料摩擦因数和磨损率均随着制动速度的增加先升高后降低,150 km/h时制动性能最好,250-300 km/h时制动性能最为稳定;制动速度一定时,随着制动压力的增加,摩擦因数先升高后降低,磨损率增大并趋于稳定,0.4 MPa时摩擦因数最大,0.8-1.0 MPa时制动性能比较稳定;铜基摩擦材料在高速制动工况下的磨损机制主要为磨粒磨损和疲劳磨损。

Cu-based friction materials were fabricated by powder on MM-1000 Ⅱtester,and the surface scratches were observed by that when the braking pressure is constant, both friction coefficient metallurgy.The friction and wear properties were tested SEM to analyze the wear mechanism.The results show and wear rate are increased firstly and then decreased with the increasing of braking speed, and the braking pads achieves the best performance at the speed of 150km/h, and the most stable braking performance at the speed between 250 km/h and 300 km/h.when the braking speed remains constant, with the increasing of the braking pressure, the wear rate is increased at first and then tends to be steady, while the friction coefficient is increased firstly and then decreased. The maximum friction coefficient occurs at the braking pressure of 0. 4MPa, stable braking performance presents between 0. 8 MPa and 1.0MPa.The main wear mechanism of Cu-based friction materials under high-speed braking condition is abrasion and fatigue wear.