Abstract：Residual austenite content in steel strongly influences the mechanical properties and thermal stability of the materials. Eddy current testing method is used to determine the residual austenite content in the steel since the relative permeability of the austenite phase, which is indicated by eddy current tests, is much smaller than that of the ferromagnetic phases. A finite element analysis method is used to simulate eddy current tests with samples having different relative permeabilities. The results show that the output signal of the alternating current (AC) bridge corresponds well with the relative permeability. The amplitude and phase of the output signal can be used as feature variables, which both having good linear correlation with the relative permeability that after processing. The residual austenite content can then be determined using the relationship between the austenite content and the relative permeability.
韩赞东, 李永杰, 李晓阳. 残余奥氏体含量涡流检测仿真与特征提取[J]. 清华大学学报（自然科学版）, 2016, 56(6): 617-621.
HAN Zandong, LI Yongjie, LI Xiaoyang. Simulation and feature extraction of eddy current tests for residual austenite content. Journal of Tsinghua University(Science and Technology), 2016, 56(6): 617-621.
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2016, Vol. 56 
