惯性制动条件对铜-石墨材料摩擦性能及第三体的影响

采用粉末冶金技术制备铜-10%石墨烧结材料,通过GF150D型摩擦试验机,在干摩擦状态及制动压力为0.51 MPa的条件下,研究不同制动方式对材料摩擦磨损性能的影响。结果表明,采用从高速到低速分段制动方式(摩擦方式A)时,随着制动速度降低,摩擦表面形成的致密第三体破碎、剥落,机械啮合力增加,摩擦因数提高;同时,摩擦表面温度下降,基体强度提高,磨损率降低。采用从高速到低速连续制动方式(摩擦方式B)的摩擦因数和磨损量均大于摩擦方式A。

Effects of Inertia Brake Conditions on Friction Properties and the Third Bodies of Copper-graphite Materials

Copper-10%graphite sintered material was prepared by powder metallurgy technology. Effects of different brake modes on friction and wear properties of copper-graphite friction materials were investigated on GF150D friction tester, under dry conditions, with brake pressure of 0.51 MPa. The results show that the friction coefficient of the material is increased with the decreasing of the brake speed at the friction mode (from high speed indirect brake to low speed). This is attributed to the breaking and peeling off of the dense third bodies on the friction surfaces, which increases mechanical engaging force. Meanwhile, the wear rate of the material is reduced, due to the decrease of friction surface temperature, which increases matrix strength. Friction coefficient and wear of friction mode B(from high speed direct brake to low speed) are higher than those of friction mode A.