Wet Friction and Wear Properties of C/C-SiC Composites During Different Braking Speeds

Carbon fibre reinforced carbon and silicon carbide dual matrix composites(C/C-SiC) were fabricated by the combination of chemical vapor infiltration(CVI) with liquid silicon infiltration(LSI).The tribological behaviors of the C/C-SiC composite were investigated using an MM-1000 friction and wear tester,at different braking speeds under dry and machine oil lubricating conditions.The results indicate that the contact angle between C/C-SiC and distilled water is about 80.5°,which means the C/C-SiC are lipophilic materials.In the CD15W-40 diesel engine oil lubrication condition,with the brake speeds increasing from 3000r/min to 6000r/min,the coefficient of friction(COF) and linear wear of C/C-SiC reach the maximum value of 0.21μm/cycle and 1.1μm/cycle respectively,at 4000r/min.When the brake speeds are 5000r/min and 6000r/min,the COF and the linear wear are 0.17 and 0,respectively.C/C-SiC maintains a relatively high COF,smooth braking curves and lower wear rate in wet conditions,which can be used as candidate materials for wet clutch of new generation of construction machinery and heavy vehicles.