Performance characteristics of electromagnetic generation and detection ofshear horizontal waves by electromagnetic acoustic transducers

The diagnosis of material degradation and the detection of discontinuities in austenitic cast stainless steel have been studied by using ultrasonic wa ves generated by an electromagnetic acoustic transducer (EMAT). A simple ci rcuit model for an EMAT generating horizontally polarized shear waves (SH w aves) was established and magnitudes of oscillations were estimated by usin g the model and experimental data. As a result, the attenuation was describ ed at two different frequencies of SH waves.