文献类型：期刊文献

英文题名：Design of Eddy Current Testing System for Metal Conductivity Based on TMR Sensor

作者：Chen, Jiaqing[1]; Hu, Minghui[1]

机构：[1] Key Laboratory of Pressure Systems and Safety, MOD, School of Mechanical and Power Engineering, East China University of Science and Technology, Shanghai, 200237, China

年份：2023

卷号：12699

外文期刊名：Proceedings of SPIE - The International Society for Optical Engineering

收录：EI(收录号：20232314188289)

语种：英文

外文关键词：Eddy current testing - Ferromagnetic materials - Metal testing - Optical variables measurement

摘要：A set of metal conductivity eddy current detection system is designed by using tunnel magnetoresistance (TMR) sensor and quadrature demodulation principle. The system uses one coil for excitation and dual TMR for receiving the magnetic field strength signals to differentiate. Through the finite element simulation, it is found that the logarithm of the phase of the difference between the magnetic field strengths at two points on the coil axis has a linear relationship with the logarithmic value of the metal conductivity. Therefore, in order to obtain the phase of the magnetic field, a quadrature demodulation system based on LabView is designed. The relative error of demodulation of magnetic field amplitude and phase of the system is within 1%. By measuring the electrical conductivity of the metal test blocks, we found that the experimental results are in good agreement with the simulation, and the relative errors of the conductivity are within 4%, which proves the feasibility of the system on detecting non-ferromagnetic materials. ? 2023 SPIE.