THIN OXIDATION RESISTANT CARBON/CARBON COMPOSITE MONITORING

NEW GENERATION HIGH-TEMPERATURE MATERIALS ARE BEING DEVELOPED FOR A HOST OF APPLICATIONS SUCH AS THE NATIONAL AEROSPACE PLANE (NASP). CARBON-CARBON COMPOSITES SHOW GREAT PROMISE FOR THIS APPLICATION BECAUSE OF THEIR HIGH STRENGTH AND STIFFNESS AT ELEVATED TEMPERATURES.IN ORDER TO FULLY UTILIZE THE HIGH-TEMPERATURE ADVANTAGES OF CARBONCARBON, OXIDATION COATINGS ARE BEING DEVELOPED AND APPLIED TO CARBONCARBON TO PREVENT OXIDATION DEGRADATION OF THE PARTS AT ELEVATED TEMPERATURES. IT IS CRITICAL THAT THESE COATINGS BE DEFECT FREE. ADVANCES IN X-RAY COMPUTED TOMOGRAPH (CT) ARE PROVIDING METHODS FOR THE EVALUATION OF STRUCTURAL MATERIALS AT VERY HIGH RESOLUTIONS. IT IS PROPOSED THAT A HIGH-TEMPERATURE OVEN SYSTEM BE DESIGNED TO INTEGRATE WITH THE TOMOSCOPE HIGH-RESOLUTION CT SCAN SYSTEM SO THAT OXIDATION COATINGS OF CARBON-CARBON COMPOSITES CAN BE FULLY EVALUATED FOR DEFECTS THROUGHOUT THE RANGE OF OPERATING TEMPERATURES. SUCH A SYSTEM WILL BE ABLE TO VIEW TINY RACKS AND VOIDS THROUGHOUT THE COATINGS WHICH COULD CAUSE RAPID OXIDATION AND FAILURE OF THE CARBON-CARBON COMPONENT. THE DESIGN OF SUCH AN INTEGRATED SYSTEM WILL REQUIRE INNOVATIVE THINKING IN OVEN DESIGN, IMAGE RECONSTRUCTION & DATA PRESENTATION.