CHARACTERIZATION OF DAMAGE IN COMPOSITE ROCKET MOTOR CANISTERS

THE INHERENT ANISOTROPY AND INHOMOGENEITY OF COMPOSITE MATERIALS MAKE DAMAGE DETECTION AND CHARACTERIZATION DIFFERENT THAN THAT OF HOMOGENEOUS ISOTROPIC MATERIALS. BOTH IN QUALITY ASSURANCE AND MAINTAINABILITY, TESTS BASED ON STRONG AND WELL UNDERSTOOD PRINCIPLES MUST BE ESTABLISHED IN ORDER TO DETECT AND QUANTIFY DAMAGE. THE DATA FROM THESE TESTS COULD SERVE AS A BASIS FOR ACCEPT-REJECT CRITERIAL FOR DAMAGE ROCKET MOTOR CANISTERS. TWO TECHNIQUES THAT APPEAR BEST SUITED FOR CHARACTERIZING DAMAGE ARE ULTRASONIC AND HIGH-FREQUENCY EDDY CURRENT METHODS. EDDY CURRENT TECHNIQUES ARE SENSITIVE TO DAMAGE NEAR THE SURFACE WHILE ULTRASONICS CAN PENETRATE THE THICKNESS OF THE ROCKET MOTOR CANISTER. THE OBJECT OF THIS RESEARCH PROGRAM INVOLVES THE DEVELOPMENT OF THE NECESSARY PRINCIPLES, TECHNIQUES, HARDWARE AND SOFTWARE TO CHARACTERIZE DAMAGE IN ROCKET MOTOR CASINGS.