Magneto-Acousto-Electrical NDT and Improved EMD De-Noising Algorithm
Lü Jingxiang1,2, Liu Guoqiang1,2
1. Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China; 2. University of Chinese Academy of Sciences Beijing 100049 China
Abstract：In this paper, a new non-destructive testing method referred to as magneto-acousto-electrical non-destructive testing (MAE-NDT) is proposed. This method has the high spatial resolution of ultrasonic testing and can overcome the skin effect of eddy current testing. It provides a new method for testing high conductivity materials. Firstly, according to the results of the study on magneto-acousto-electrical tomography in biological tissues, the forward problems of the sound field and the electromagnetic field were derived. So the feasibility of the method was proved. Secondly, aiming at the noise of the detected signals, the composition and characteristics of noise in magneto-acousto-electrical nondestructive testing signals were analyzed. A hybrid threshold EMD de-noising algorithm which combines the advantages of EMD-DT and EMD-IT was proposed. Finally, an experimental system was designed and the magneto-acousto electrical defect signal was measured. Therefore, the feasibility of the method was further verified. The results of simulated and measured signals show that the improved EMD de-noising method has better de-noising effect, improves the signal to noise ratio effectively.
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2018, Vol. 33 
