An improved longitudinal wave EMAT based on the shielding effect

Issue title: Proceedings from the 16th International Symposium on Applied Electromagnetics and Mechanics (ISEM 2013)

Guest editors: Xavier Maldague and Toshiyuki Takagi

Article type: Research Article

Authors: Wu, Xinjun^{a; *} | Ding, Xu^a | Wang, Li^a

Affiliations: [a] School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, China | Université Laval, Canada | Tohoku University, Japan

Correspondence: [*] Corresponding author: Xinjun Wu, School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China. Tel.: +86 27 8755 9332; Fax: +86 27 8755 9332; E-mail: xinjunwu@mail.hust.edu.cn

Abstract: 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.

Keywords: Electromagnetic acoustic transducers (EMATs), longitudinal wave, shielding effect, eddy current, copper sheet

DOI: 10.3233/JAE-141834

Journal: International Journal of Applied Electromagnetics and Mechanics, vol. 45, no. 1-4, pp. 227-233, 2014