Thermal properties of carbon fiber reinforced carbon matrix, C/C (Carbon fiber/Carbon), composites were determined in the temperature range between 20 C and 2,000 C. As thermal properties, specific heat, thermal conductivity, thermal diffusivity, coefficient of thermal expansion, and emissivity were evaluated as a function of temperature. Three kinds of laminate type C/C composites, unidirectional, cross-ply, and quasi-isotropic, were examined. In addition to representation to temperature dependence of above-mentioned thermal properties, comparison was made between measured thermal properties with theoretical predictions. Main difficulty in the prediction of the thermal properties were to simulate complex microstructures of the C/C composites, i.e., porous structure and dispersed transverse cracks. As far as thermal conductivity and coefficient of thermal expansion were concerned, it was shown that the Eshelby model was effective and gave reasonable prediction, because of its versatility to simulate the complex microstructure.
C/C複合材料の高温物性
