EFFECT OF OXIDATION-INDUCED WEIGHT LOSS ON MECHANICAL PROPERTIES OF TWO-DIMENSIONAL CARBON-CARBON COMPOSITES~@

摘要

For several years Honeywell International Inc. (formerly AlliedSignal Inc.) has been developing Carbon-Carbon materials and components intended for 10,000+ hours of use in oxidizing environments, at temperatures up to 650°C. Presented here are (a) recent oxidation rate data at 316-399°C and (b) room-temperature measurements of the tensile strengths and Young's moduli of 181 unprotected, single-ply, two-dimensional, woven, pitch-based-fiber C-C coupons, as a function of oxidation-induced weight losses. The oxidation kinetics are supra-linear with time and exponential (Arrhenius) with temperature, with an activation energy of 2.1 eV. The above mechanical properties are unchanged by the air exposures, within statistical accuracy, up to and including 480 h at 385°C, which corresponds to an average weight loss of 1.5%.