Metal matrix composites (MMC's) made by powder metallurgy offer the possibility to tailor the thermal properties of the metal by adding carbon based reinforcements, e.g. natural graphite flakes. The microstructure, thermal conductivity (TC), coefficient of thermal expansion (CTE) and the damping behaviour of the composites based on Cu-C, Al-C, Fe-C and W-C will be displayed and discussed. The produced composites exhibit TC in the range of 300 W/ mK to 550 W/ mK combined with a reduced CTE in the range of 3 ppm/ K to 10 ppm/ K and a high mechanical damping. The tungsten- graphite composites represent a TC of 400 W/ mK and a low CTE of 3 to 5 ppm/ K. Anisotropy of the properties of metal-graphite composites due to intrinsic anisotropic properties of the graphite flake must be considered and is displayed for the CTE.
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