不同刹车压力下C/C复合材料的摩擦磨损性能

Friction and Wear Properties of Carbon/Carbon Composites under Different Braking Pressure

研究了粗糙层和光滑层2种不同热解炭与树脂炭混合基体炭/炭复合材料在不同制动压力下的摩擦磨损性能,且对摩擦表面与磨屑进行了SEM观察和分析,并采用X射线衍射与激光喇曼光谱测定了在不同刹车压力下摩擦表面的石墨化度。研究结果表明:C/C复合材料的摩擦因数由摩擦表面所形成的摩擦膜所决定,随着刹车压力的增大,摩擦膜更完整平滑,摩擦因数呈降低趋势,磨损则随刹车压力的增大而呈增大趋势;粗糙层结构C/C复合材料即使在高制动压力下,仍能具有较高的摩擦因数,显示出优良的高压摩擦性能;高压下摩擦表面会发生应力石墨化作用,这是高压下摩擦因数下降的原因之一。

Friction and wear properties of C/C composites with rough laminar (RL) and smooth laminar(SL) microstructure under different braking pressures were studied. In order to inquire into the worn mechanisms, the morphology of worn surfaces and wear debris were observed through scanning electron microscopy and the graphitization degree of worn surface were examined by X-ray diffraction and Raman spectrum. The results show that with the increase of braking pressure, the coefficient of friction shows the trend of decrease, but the mass loss shows the trend of increase; the friction and wear properties of C/C composites with RL pyrolytic carbon can maintain fairly well even under the largest braking pressure; the graphitization degrees of worn surfaces increases with braking pressure, which is caused by the shear stress assisting graphitization; the increase of graphitization degree is helpful to the decrease of friction.