文献类型：会议论文

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]East China Univ Sci & Technol, Sch Mech & Power Engn, MOD, Key Lab Pressure Syst & Safety, Shanghai 200237, Peoples R China

会议论文集：3rd International Conference on Sensors and Information Technology (ICSI)

会议日期：JAN 06-08, 2023

会议地点：Xiamen, PEOPLES R CHINA

语种：英文

外文关键词：Conductivity; eddy current testing; TMR sensor; quadrature demodulation

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.