Abstract:
C/C materials were prepared by liquid-vaporized and thermal-gradient CVI, and C/C-SiC composite with a density of 2.13~2.28 g/cm
3 was prepared by reactive melt infiltration(RMI) in this paper. The microstructure of C/C-SiC was examined using XRD and OM, and its mechanical properties (flexural strength, compressive strength, hardness and fracture ductility), friction and wear characteristics were investi-gated. The results show that C/C-SiC is composed of C, SiC and Si. The lower the density of C/C, the higher the density of corresponding C/C-SiC. By graphitization, the flexural strength of C/C-SiC decreased from 203~275 MPa to150~210 MPa and the compressive strength decreased from463~607 MPa to 403~536 MPa, but the fracture ductility increased from 6.6~8.5 MPa·m
1/2 to 7.3~9.2 MPa · m
1/2. During the sliding friction of C/C-SiC disc to SiC pin, the friction coeffici~ent was about 0.19. By graphitization, the friction coefficient decreased to 0.14~0.15, but the average volume loss rate increased from 3.4×10
-3~5.0×10
-3mm
3/h to 7.9×10
-3~9.8×10
-3mm
3/h.