OXIDATION PROPERTIES OF VAPOR GROWN FIBERS

REQUIREMENTS FOR HIGH PERFORMANCE AIRCRAFT MANDATE THE DEVELOPMENT OF HIGH TEMPERATURE COMPOSITE MATERIALS. ALTHOUGH GRAPHITE COMPOSITES HAVE MANY ATTRACTIVE MECHANICAL AND THERMAL PROPERTIES, THESE PROPERTIES DEGRADE SUBSTANTIALLY WITH OXIDATION. A NOVEL GRAPHITE FIBER HAS BEEN DEVELOPED WHICH HAS SUPERIOR PROPERTIES FOR TENSILE STRENGTH AND MODULUS. ALTHOUGH OXYDATION CHARACTERISTICS FOR THIS FIBER HAVE NOT BEEN MEASURED, THE UNIQUE LAMELLAR GRAPHITIC STRUCTURE IS EXPECTED TO YIELD A MATERIAL HIGHLY RESISTANT TO OXIDATION AT ELEVATED TEMPERATURES. THE PROPOSED RESEARCH WILL MEASURE THE OXIDATION PROPERTIES OF THIS MATERIAL AS A FUNCTION OF TEMPERATURE IN SEVERAL PREPARATIONS DESIGNED TO ENHANCE THE OXIDATION RESISTANCE OF THE FIBER. PHASE I RESEARCH WOULD ESTABLISH THE FEASIBILITY OF USING ANY OF THESE PREPARATIONS IN HIGH TEMPERATURE COMPOSITE STRUCTURES, AND PHASE II RESEARCH WOULD EXTEND THIS RESEARCH BASE AND EXPLORE COMPOSITE MANUFACTURE.