C/C-SiC与HT250灰铸铁摩擦副的制动效能

Effectiveness of C/C-SiC and HT250 gray cast-iron friction couples

采用化学气相渗透和熔硅浸渗相结合的方法制备C/C-SiC制动材料,在惯性台架试验机上对C/C-SiC与HT250灰铸铁摩擦副进行性能检测。结合材料组织结构,对制动效能与制动初速度、摩擦因数、制动压力的相关性及摩擦副摩擦机理进行分析。结果表明:恒力矩制动实验中,在制动力矩相同的条件下,摩擦因数随制动初速度增大而减小。在制动力矩由280 Nm增加到680 Nm的过程中,制动初速度为50k m/h和100 km/h时,摩擦因数随压力增大而增大;但制动初速度为100 km/h时,摩擦因数增大的幅度小,压力增大的幅度大;制动初速度为130 km/h时,摩擦因数随制动压力的增大而减小,压力对制动起主导作用。

C/C-SiC braking composites were fabricated by Chemical Vapor Infiltration and Reactive Melt Infiltration methods.The inertial brake dynamometer was used to study the braking behavior of the C/C-SiC and HT250 friction couples,and relation among the C/C-SiC composites structure,the initial braking speed,braking pressure,and friction coefficient as well as the friction mechanism of the friction couple were investigated.The results show that when brake torque is constant,the friction coefficient decreases with increasing initial braking speed.As the braking torque varying from 280 Nm to 680 Nm,the friction coefficient increases with increasing braking pressure when the initial braking speeds are 50 km/h and 100 km/h;while when the initial braking speed is 100 km/h,the friction coefficient increases slightly and braking pressure increases obviously;but as the speed is 130 km/h,the friction coefficient decreases with increasing braking pressure.