Properties of Graphite Fiber Nonmetallic Matrix Composites

Abstract

Recent results of development and characterization of high perform ance graphite reinforced plastic composites are reviewed. Fabrication and characterization of epoxy matrix composites utilizing a variety of types and forms of high modulus graphite fibers as the reinforcement are discussed. Data relating interlaminar shear strength of composites to fiber surface condition and the effectiveness of fiber treatments to increase interlaminar shear strengths are reported. Graphite fibers in an increasing number of forms have been in vestigated as composite reinforcements. These forms include: con tinuous yarns of varying twist, short lengths of 10,000 filament tows, very long lengths (ca. 1000 feet) of tows, and continuous staple yarns of long (ca. 7 inch) fibers. A considerable range of average fiber proper ties is involved, such as moduli of 25 to 65x10⁶ psi, tensile strengths of 150 to 450x10³ psi, and densities of 1.4 to 2.0 g/cc.