| A copper matrix friction material was prepared through powder metallurgy, and the friction and wear properties were investigated on GF150D friction tester, with tin content of0-14%under velocities range of200-3000rpm and brake pressures range of0.38-0.63MPa. The experiment results show that:The friction coefficient of the material with tin addition is significantly improved, and the friction coefficient reaches the highest value when tin content is about12%. The content of tin in the range of8-12%can significantly reduce the wear rate under the condition of high-speed friction, which is due to the improved strength of the material. Under condition of low velocity, the friction coefficient is increased with increasing brake pressure, and the friction coefficient is reduced with increasing brake pressure at high velocity. However, the friction coefficient is reduced with high velocity and great brake pressure due to the increase in friction temperature, the third body quantity and matrix softening and plasticity.Comparison of two coefficients which is dry friction and wet friction, the friction coefficient under the condition of low velocity is quite different. On the one hand, the water film reduce the friction surface temperature, on the other hand, water film has the effect of lubrication. The coefficient of friction under high velocity is little different, because high temperature water vaporize quickly, reduce the role of lubrication of water.The order also can affect the friction coefficient of friction in the friction process, and from high to low friction coefficient is lower than the friction coefficient from low to high. Also has the effect of cooling conditions on the coefficient of friction, and without cooling coefficient is lower than the coefficient under the condition of cooling. |
PDF Full Text Request