Abstract: On m²000 wear machine, coupled with 40Cr steel, four kinds of C/C composites with different carbon matrix structures have been tested under different loadings for friction and wear characteristics. The results show: the RL（rough layer） structure sample gets the highest friction coefficient 0.151～0.165 and fluctuating with loading increase;and the SL（smooth layer） structure sample gets the lowest friction coefficient 0.105～0.118 and decreasing slowly with loading increase. With time prolonging, the friction coefficient of RL structure sample decreases under high loading, while that of SL structure sample increases a little except under 60N. Under all the loadings, the friction coefficient of resin carbon densified sample decreases with time prolonging, but that of SL+resin carbon structure sample shows the variety trend being different under different loadings. The bulk wear loss of RL structure sample is the highest which could reach 1.61 mm³ under 150N, and that of SL+resin carbon structure sample is the least. The SEM observations show: with loading increase, the wear surface of RL sample changs only a little, while that of the resin carbon sample exhibits more and more severe surface fiber drawn phenomenon, and the SL+resin carbon structure sample exhibits more and more smooth wear surface.

Key words: C/C composites, carbon matrix, friction, wear