湿式C/C制动材料的摩擦特性及其数值模拟

利用多元耦合场CVI工艺将炭毡增密至1.58 g/cm3,再进行树脂浸渍/炭化增密至1.85 g/cm3制备C/C复合材料。测试由其制成的摩擦实验环的湿式摩擦磨损性能,并利用软件建立的有限元模型对2 500 r/min及1.5 MPa时摩擦实验环的温度场分布进行模拟。结果表明:该湿式摩擦材料的摩擦因数在0.07~0.13间波动,当初始转速恒定时,摩擦因数随刹车压力的增大而减小;当刹车压力恒定时,摩擦因数先增大后减小。建立了C/C复合材料湿式制动过程模型,通过模拟获得了制动盘的各个部位温度场在本模拟研究中呈岛形分布,最高温度出现在0.875 s,这为制动材料的设计提供了参考。

Wet friction properties and numerical simulation of C/C composites

The carbon felt was densified to 1.58 g/cm3 with multi-factor coupling fields CVI,and then it was impregnated with resin/carbonized to 1.85 g/cm3 to make the low cost C/C composites.The wet friction and wear properties were tested by friction ring.The temperature distribution of the friction ring was simulated under the condition of 2 500 r/min and 1.5 MPa.The results show the friction coefficient of wet friction material is in the range of 0.07?0.13.The friction coefficient decreases with the increase of brake pressure for constant initial rev.The friction coefficient increases first,and then decreases with initial rev increasing.The model is established by finite element software for thermal simulation of the wet brake process.The shape of temperature distribution likes an island,and the highest temperature emerges at 0.875 s in this simulation.The results are supposed useful to design better brake materials.