Thermal expansion and thermal conductivity of continuous carbon fibre reinforced copper matrix composites

Carbon fibre reinforced copper matrix composites with adequate quality are promising materials in applications where heat transport plays an important role, e.g. as heat sinks for the electronics industry. Apart from good thermal conductivity, a low coefficient of thermal expansion is also important. In order to produce the material in an economical manner, the approach here used continuous PAN-type carbon fibres (Torayca T300). The fibres have been continuously copper coated, and unidirectional and cross-ply samples have been produced by diffusion bonding. The coefficient of thermal expansion and thermal conductivity of the material have been investigated. Thermophysical properties have been measured in both longitudinal and transverse directions to the fibre orientation. The results showed that the cross-ply Cu-C/sub f/ MMC produced from the Torayca T300 fibres may be a suitable candidate for heat sinks because of its good thermophysical properties, e.g. in-plane thermal conductivity (/spl ap/145 W/m.K), through-thickness conductivity (/spl ap/50 W/m.K), low density (/spl ap/5 g/cm/sup 3/) and the low coefficient of thermal expansion (8-9/spl times/10/sup -6/ K/sup -1/).