Thermal conductivity, electrical conductivity and specific heat of copper-carbon fiber composite

We have developed a new copper-carbon fiber composite which possesses properties of copper, i.e., excellent thermal and electrical conductivities, in combination with a property of carbon fiber, i.e., a small thermal expansion coefficient. The composite properties can be controlled by the amount, type and orientation of the carbon fibers they contain. Therefore, this composite is considered to be useful as an electrical material.
The effects of volume and arrangement of fibers on the thermal conductivity, electrical conductivity and specific heat of the composite were studied. The results obtained were as follows:

(1) The thermal and electrical conductivities of the composite became smaller as the volume of carbon fibers increased, and they were also influenced by the fiber arrangement.

(2) The above conductivities could be calculated by careful application of the “rule of mixtures” for composites.

(3) The specific heat of the composite was dependent not on the fiber arrangement but on the fiber volume.

(4) In thermal fatigue tests, no degradation in electrical conductivity was observed.