Metal matrix composite material which co-containing carbon fibers of micron-sized and nano-sized

摘要

An object of the present invention is to provide a metal-based carbon fiber composite material that exhibits an improved thermal expansion coefficient and an improved thermal conductivity, and is smaller in weight. The metal-based carbon fiber composite material of the present invention comprises a metal and a carbon fiber comprising a micron carbon fiber and a nanofiber; the composite material having a first surface; the micron-size carbon fiber being oriented in one direction parallel to the first surface of the composite material, and being continuous from one end to the other end; at least 80% of the nanofiber being oriented at an angle within 30° with respect to the first surface; and the nano-size carbon fiber being oriented randomly in a plane parallel to the first surface. In the metal-based carbon fiber composite material, a surface region thereof may comprise a smaller amount of the micron carbon fiber than that in another region, or comprise no micron carbon fiber; and the nanofiber may have an orientation parallel to the surface of the composite material. The present invention provides a method for producing these composite materials.