On the basis of analyzing testing principle of ultrasonic guided circumferential wave transducer based on the Lorentz mechanism

influence of transducer parameters on amplitude of detected signal is studied by experiments

and parameters of transducer are determined according to experimental result. Electromagnetic ultrasonic wave circumferential guide transducers are designed and fabricated. Performance test result of transducer shows that the transducer can detect the through-hole defect with 5 mm diameter.