A MEMS phased array transducer for ultrasonic flaw detection

Metal structures can fail because of fatigue crack propagation or because of section loss from corrosion. Regular inspection is required to detect such failures. We report here progress toward the development of MEMS-based transducers for ultrasonic flaw detection, to be permanently mounted at critical locations on structures. In a complete system, a single piezoelectric element will be used to emit a pulse of ultrasonic energy and an array of MEMS detectors will be used to detect echoes from nearby surfaces or flaws. In this paper, we report initial characterization of MEMS ultrasonic transducers, coupling of these transducers to a solid structure, and the use of multiple transducers to detect the distance and angular location of an ultrasonic source.

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