Carbon cloth/carbon matrix composites were prepared by chemical vapor deposition process. Microstructures of carbon matrix and tensile behaviors of the composites were investigated. The various microstructures of carbon obtained in this work fall into three major types identified as smooth laminar, rough laminar and dark laminar.
A typical load-extension curve for tensile tests of composites shows three different stages and the cracks were observed on the surface of the specimen released from stage II and stage III.
It is shown from the fractography that the debonding of fiber/matrix interfaces and the pull-out of broken fibers occur as the crack propagates through the composites.
The mechanical properties such as tensile strength, modulus and elongation to fracture were significantly affected by the relative amount of the matrix carbon.
The role of circumferrential microcracks formed during the cooling after deposition was considered by controlling the cooling rate of composites and related to the microstructures of the matrix carbon.
