Thermophysical properties and microstructure of graphite flake/copper composites processed by electroless copper coating

•GF–copper composites were fabricated using a sparking plasma sintering, which involves coating GF with copper, using electroless plating technique.•The oriented graphite flake distributed homogeneously in matrix.•With the increase of flake graphite from 44 to 71 vol.%, the basal plane thermal conductivity of composites increases from 445 to 565Wm−1K−1 and the thermal expansion of composites decreases from 8.1 to 5.0.•The obtained composites are suitable for electronic packaging materials. This study focuses on the fabrication of thermal management material for power electronics applications using graphite flake reinforced copper composites. The manufacturing route involved electroless plating of copper on the graphite flake and further spark plasma sintering of composite powders. The relative density of the composites with 44–71 vol.% flakes achieved up to 98%. Measured thermal conductivities and coefficients of thermal expansion of composites ranged from 455–565Wm−1K−1 and 8 to 5ppmK−1, respectively. Obtained graphite flake–copper composites exhibit excellent thermophysical properties to meet the heat dispersion and matching requirements of power electronic devices to the packaging materials.