Abstract: Novel carbon-carbon laminate composite materials capable of significantly increased strengths in at least one predetermined direction of load are disclosed. The composites can comprise plies of resin impregnated woven carbon or graphite cloth material in combination with resin impregnated carbon or graphite filament unidirectional tape or can be fabricated from the unidirectional tape alone. Generally the unidirectional reinforcement of the tape plies provides higher strengths and moduli in specific directions which can be controlled during lay up of parts. The processes for obtaining the beneficial increase strength of unidirectional tape ply materials while avoiding fabrication problems resulting therefrom are also disclosed.

Abstract: Disclosed is a method of making carbon/carbon composites by pyrolytic conversion of a carbonizable liquid in a pre-formed graphite body to form an amorphous carbon reinforcing matrix. Graphite fabric saturated with a carbonizable liquid is formed into the shape of the desired end product body and placed in a flexible bag. The bag is evacuated to compress the formed body and the bagged body subjected to external pressure and heated. When the carbonizable liquid is heated to the curing temperature, the external pressure is reduced, causing volatile materials in the liquid to expand and form an interconnected pore structure. The formed body is thereafter heated to a temperature in excess of the curing temperature to further remove volatile materials therefrom. The cured rigid body is then transferred to a pyrolyzing furnace and rapidly heated in an inert gaseous environment directly to about 1500.degree. F. to pyrolyze the carbonizable material and form an amorphous carbon matrix.