炭/炭复合材料的摩擦磨损性能

Wear properties and friction surfaces of the C/C composites

选取由CVD预增密至一定密度 ,再进行树脂浸渍 炭化补充增密至 1.85g cm3的炭 炭复合材料作摩擦环试样 .测试了该试样在一系列刹车速度时的摩擦磨损性能 ,并对其摩擦面及磨屑进行了SEM观察 ,对摩擦面进行显微喇曼光谱分析 .研究结果表明 :炭 炭复合材料的摩擦磨损性能随刹车速度的变化而发生显著变化 ,在 10m s时出现最高峰 ,在 2 5m s出现亚高峰 ;磨损量随刹车速度的增加而增加 ,而氧化磨损在刹车速度为 2 5m s时开始大量产生 ,在 2 8m s时达最大值 .其摩擦表面形貌、结构及磨屑亦有较大差别 .刹车速度从 5m s升至 2 0m s时 ,摩擦面石墨化度降低 ,石墨结构向无定型碳结构转变 ,但在高速时石墨化度反而升高 。

A series of brake experiments at different brake velocities have been made for carbon carbon composite which was densificated by resin impregnation after pre densificating to initial density by CVD(chemical vapor deposition).SEM graphs of the friction surface and the wear debris and the analysis of micro Ramam spectra of the friction surface are given. The results show that, the friction coefficient braking at the speed of 10 m/s is the highest and that at 25 m/s is the second highest and the wear rate increases with the braking velocity. The friction and wear properties are connected closely with the surface morphology and the structure of the friction surface and the wear debris. The graphitization degree of the friction surface is increased at a high braking velocity.