Abstract
We report on the influence of the interface between the metal matrix and ceramic reinforcement on the thermal expansion and thermal conductivity of three composites – QE22 with 25 vol.% of SiC particles, QE22 with 20 vol.% of Saffil fibres and QE22 with 20 vol.% of SiC and 5 vol.% of Saffil fibres – which was investigated in the temperature range of 20–380°C. The composites become macroscopically deformed at room temperature due to different thermal expansion coefficients of two components. The thermoelastic stress field in the matrix is influenced by the matrix plastic deformation near the interface. The strongest changes in the thermal expansion coefficient and thermal conductivity occur at temperatures at which the thermoelastic stress releases with the reduction of the plastic deformation.

Key words
magnesium composites, thermal expansion, thermal conductivity, thermal strain

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