Optimum excitation of the Lamb wave modes in NDE

摘要

This paper presents a study of the use of EMAT (Electromagnetic Acoustic Transducer) to generate and detect the single Lamb wave in the different thickness steel plate. Using an EMAT with a given wavelength, the desired single Lamb wave mode are generated and detected by controlling the center frequency of narrowband signals, and the center frequency of waves is about from 0.18MHz to 1MHz. The experimental work was performed on the steel plate of different thickness, and the results indicated this EMAT configuration for excitation of the single Lamb wave is valid.