论文信息 - An improved longitudinal wave EMAT based on the shielding effect

An improved longitudinal wave EMAT based on the shielding effect

Electromagnetic acoustic transducer (EMAT) has been used in many industrial areas due to its non-contact nature. However, the longitudinal wave EMAT is rarely employed because it is difficult to be generated. An improved longitudinal wave EMAT is proposed in this paper. By inserting the copper sheet between the coil and the test specimen, the eddy currents induced in the test specimen are changed and the components of the eddy currents for generating the shear wave are effectively suppressed. The performance of the EMAT is tested by the experiment.

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