Sliding Friction and Wear Behavior of C/C Composite under Low-energy Loads

The sliding friction and wear behavior of needled-carbon fiber felt C/C composites were tested using a MM-200 ring-block frictional tester at different rotational speeds and loads.The wore surface morphologies were observed under a digital camera and the scanning electron microscopy(SEM).The friction coefficient is relatively stable under the low-speed conditions,but the wear rate increases with increasing load.When the speed is high,the specimen with low load also shows low friction coefficient,but the wear rate increases.When the load is high,a peak value of friction coefficient occurs at the fifth minute of wear,and goes back to stable,but high afterwards.And the wear rate increases dramatically,indicating a change of wear mechanism.The friction surface of C/C composite which is parallel to felt plane has a relatively low wear rate,i.e.a better friction and wear performance.