Quantitative evaluation of stress concentration in ferromagnetic steels based on residual magnetic field measurements

摘要

The object of this research is to investigate variations in the residual magnetic field (RMF) on the surface of X80 and 30Cr steel specimens with circular through-holes using tensile tests. Two magnetic evaluation parameters are defined to characterise the quantitative relationship between the abnormal magnetic changes and the applied loads. The correlation between the evaluation parameters and the applied load is influenced by the steel materials. The magnetic concentration factors based on the evaluation parameters are found to be exponentially correlated with the stress concentration factors. This research demonstrates the potential possibility of quantitative defect identification of ferromagnetic steels using RMF measurements.