Ultrasonic Behavior of Rocket Fuel Model Using Multi-Channel Pulser and Laminated Transducer

Ultrasonic measurements for composite materials, concrete and welding structure of inconel alloy are difficult because of the highly acoustic attenuation. For these materials low-frequency ultrasound is generally used to avoid the larger attenuation because attenuation factors of scattering and absorption both depend on frequency. However kHz band ultrasound sometime make troubles due to the lower directivity and to lower signal to noise ratio. The authors have studied large amplitude ultrasonic transmission systems of MHz range for nonlinear ultrasound measurement combining the multi-channel pulser and laminated transducer[1,2] In this study, we tried to investigate the availability of the large amplitude ultrasound incidence for highly attenuated materials using the model specimen of rocket fuel model. We compared the transmission echoes through the specimen using the conventional ultrasonic pulser and the multi-channel pulser system using laminated transducer.