1. Key Laboratory of New Technology of Nonferrous Metals and Materials Processing, Ministry of Education, Guilin University of Technology, Guilin 541004, China; 2. Collaborative Innovation Center for Exploration of Hidden Nonferrous Metal Deposits and Development of New Materials in Guangxi, Guilin University of Technology, Guilin 541004, China; 3. Guangxi Shenglong Metallurgy Co., Ltd., Fangchenggang 538029, China
Abstract：The response mechanism of carbon steels with different phase compositions and phase fractions to the electromagnetic signals was investigated using U-shaped electromagnetic sensors and multi-frequency single-channel electromagnetic measuring instruments based on multi-frequency electromagnetic non-destructive testing technology. The corresponding relation between electromagnetic signal of zero crossing frequency and microstructure was constructed. The phase composition and phase volume fractions of four carbon steels (Q235B, Q355B, 45# and T8) and two wear-resistant steels (NM400 and NM500) were characterized. The results showed that the phase volume fraction of carbon steels could be characterized by the electromagnetic signal of zero crossing frequency, which provided a basis for on-line and real-time monitoring and regulation of the phase composition as well as phase volume fraction of carbon steels.
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2023, Vol. 41 
