STUDY OF THE MANUFACTURE AND PROPERTIES OF C/C COMPOSITES FROM CARBON CLOTH

In order to decrease the cost of C/C composites from rapid densification and to decrease the cost of equipment, C/C composites derived with rapid densification were manufactured through cycles of impregnation under medium pressure and carbonization. In this process, carbon cloth reinforced in Z direction was used as reinforcement, and both mesophase pitch with different softening point and modified pitch with high carbon yield as impregnants. The process of impregnation was studied, and properties and fracture morphology of the resultant C/C composites were also measured. The result shows that pitch with high carbon yield, either mesophase pitch or modified pitch, is excellent impregnant for C/C composites and helpful to rapid densification. After 8 times cycle (about 2 weeks), the density of C/C composites reached 1.76?g/cm 3 from 0.84?g/cm 3. The C/C composites from laid up carbon cloth have good mechanical properties, and the mechanical properties increased with the density. When the density became 1.76?g/cm 3, the tensile strength is 87.03?MPa, flexural strength is 113.56?MPa, and compressive strength is 199.49?MPa.