NONDESTRUCTIVE ANALYSIS OF GRAPHITE REINFORCED MATERIALS (GRM)

THE ADVENT OF GRAPHITE REINFORCED COMPOSITES HAS LED TO MAJOR ADVANCES IN AEROSPACE TECHNOLOGY. SUCH COMPOSITE MATERIALS ARE BECOMING ESSENTIAL TO MODERN FLIGHT TECHNOLOGYDUE TO THEIR EXCEPTIONALLY HIGH STRENGTH-TO-WEIGHT RATIOS WHEN COMPARED TO METALS AND ALLOYS. MANY AIRCRAFT AND ROCKET COMPONENTS ARE CURRENTLY MADE FROM THESE NEW MATERIALS AND MANY NEW DEVELOPMENTS REQUIRE THEIR UNIQUE PROPERTIES. THE USE OF GRM IN AEROSPACE APPLICATIONS HAS RESULTED IN HIGHER QUALITY MATERIALS TO MEET MORE DEMANDING PERFORMANCE SPECIFICATIONS. AS A RESULT, THERE IS A REQUIREMENT FOR ADVANCES IN NONDESTRUCTIVE INSPECTION EQUIPMENT TO PROVIDE ACCURATE REAL TIME COMPOSITION ANALYSIS OF THESE COMPOSITES. SINCE THE PROPERTIES OF THESE COMPOSITES ARE STRONGLY DEPENDENT ON THE RATIO OF GRAPHITE FILLER TO BINDING RESIN, A RELIABLE NONDESTRUCTIVE TECHNIQUE FOR THE DETERMINATION OF THE RESIN TO GRAPHITE RATIO OF GRM IN BOTH PREPREG AND CURED FORMS IS ESSENTIAL. TO ASSURE THAT GRM ARE SUITABLY MADE, WE PROPOSE TO DEVELOP A RADIOMETRIC NONDESTRUCTIVE INSTRUMENT WHICH WILL ALLOW THEACCURATE DETERMINATION OF RESIN CONSTANT IN BOTH PREPREG ANDFINAL COMPOSITES. THE INSTRUMENT WILL BE USEFUL NOT ONLY FOR QUALITY ASSURANCE BUT ALSO FOR FAILURE ANALYSIS OF KEY COMPONENTS AND STRUCTURES. ALTHOUGH THE PRIMARY FOCUS OF THE PROJECT WILL BE ON AEROSPACE COMPONENTS, THE METHOD WILL BE USEFUL FOR MANY OTHER APPLICATIONS.