A high thermal conductivity/low coefficient of thermal expansion thermally conductive composite material for heat sinks and an electronic apparatus comprising a heat sink formed from such composites. The thermally conductive composite comprises a high thermal conductivity layer disposed between two substrates having a low coefficient of thermal expansion. The substrates have a low coefficient of thermal expansion and a relatively high modulus of elasticity, and the composite exhibits high thermal conductivity and low coefficient of thermal expansion even for composites with high loadings of the thermally conductive material.