Electrical and thermal conductivities of the Cu–CF composite

Abstract

The paper presents a new approach in the field of metal–matrix composite characterisation where an electrical conductivity measurement was used to calculate the electron part of composite thermal conductivity by using the Wiedemann–Franz law. The electrical and thermal conductivities of the composite were characterised and their relationship was analysed. Results showed that in comparison with simple analytical models, this method can also be used for predicting the thermal conductivity of the copper matrix–continuous carbon fibre composite in a transverse direction. The unidirectional composite was produced by diffusion bonding and contained 40–60 vol.% of unidirectional fibres. Experiments were performed in directions parallel and normal to the fibre orientation and showed that with an increasing ratio of fibre volume, both thermal and electrical conductivities decreased from 221.6 W/m·K to 38.7 W/m·K and from 35.8 MS/m to 5.3 MS/m, respectively.