Patent ID: 7923103

Claim:
A composite material having a high thermal conductivity and a small thermal expansion coefficient, which is obtained by impregnating a porous graphitized extrudate with a metal; said composite material having such anisotropy that said thermal conductivity and said thermal expansion coefficient are 250 W/mK or more and less than 4×10 −6 /K, respectively, in an extrusion direction; and that said thermal conductivity and said thermal expansion coefficient are 150 W/mK or more and 10×10 −6 /K or less, respectively, in a direction perpendicular to said extrusion direction; wherein an ash content in said porous graphitized extrudate is 0.5% by mass or less; and wherein the ratio of the thermal expansion coefficient in the perpendicular direction to that in the extrusion direction is 2 or more.