Research on Testing Method of Electromagnetic Acoustic Total Focusing Method Imaging

doi:10.3901/JME.260109

Abstract

Abstract: An electromagnetic acoustic total focusing imaging testing method based on the total focusing method(TFM) is proposed. Using racetrack coils as array elements, two eight-element transverse wave linear arrays EMAT with different element widths are designed. At the same time, an experimental system of electromagnetic acoustic full matrix data sampling was established. Through experiments, the full-matrix data of electromagnetic acoustic testing of artificial defects are collected at different positions of the specimen, and the defects were detected by TFM imaging through post-processing. The law of defect detection by electromagnetic acoustic TFM imaging is studied, and the factors that affect electromagnetic acoustic TFM imaging detection are preliminary analyzed, and the influence of linear array EMAT with different array element widths on electromagnetic acoustic TFM imaging is compared and analyzed. The results show that electromagnetic acoustic TFM can effectively detect defects in different areas of the specimen, which proves the feasibility and effectiveness of electromagnetic acoustic to achieve total focusing method imaging. The TFM imaging of the linear arrays EMAT is affected by the diffusion of the ultrasound field radiated by the array element, and the linear arrays EMAT with a smaller array element width in the same detection area can obtain a better defect imaging effect.

Key words: electromagnetic ultrasound, full focus imaging, linear array EMAT, full matrix data, radiated sound field

CLC Number:

TB553

ZHENG Yang, ZHANG Zongjian. Research on Testing Method of Electromagnetic Acoustic Total Focusing Method Imaging[J]. Journal of Mechanical Engineering, 2026, 62(4): 98-106.

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