文献类型：期刊文献

英文题名：Application of coded excitation in the Rayleigh wave detection of aluminum plates with narrow-magnet EMAT

作者：Lin, Junjie[1]; Guo, Xinfeng[1]; Liu, Lishuai[1]; Xiang, Yanxun[1]; Xuan, Fu-Zhen[1]

机构：[1] Shanghai Key Laboratory of Intelligent Sensing and Detection Technology, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China

年份：2024

卷号：2822

期号：1

外文期刊名：Journal of Physics: Conference Series

收录：EI(收录号：20244617347768)

语种：英文

外文关键词：Acoustic fields - Acoustic noise - Acoustic transducers - Aluminum sheet - Electric excitation - Lifting magnets - Ultrasonic testing - Ultrasonic waves

摘要：The poor generation efficiency causes the low signal-to-noise ratio (SNR) of the electromagnetic acoustic transducers (EMATs). The magnetic fields at the edges of the magnet are fully utilized in the narrow-magnet EMAT to generate Rayleigh waves of higher amplitudes than the conventional EMAT. This paper applies the coded excitation technology to narrow-magnet EMAT to further improve the SNR and the lift-off performance in aluminum plate detection. The main phase encoding methods are Barker code and Golay code. Compared with the conventional tone-burst excitation method, both coded excitation technologies can effectively improve the SNR of the Rayleigh wave. Theoretically, the received Rayleigh waves using the Golay-coded excitation method have no sidelobe, which is different from the case using the Barker code. Hence the Golay-coded excitation achieves higher SNR in the received ultrasonic waves. In addition, the application of the Golay-coded excitation can also effectively improve the lift-off performance of the narrow-magnet EMAT. ? 2024 Institute of Physics Publishing. All rights reserved.