Research on Corrosion Circumferential Area Characterization for Steel Cable Bundle Based on Metal Magnetic Memory

Due to the large size of the steel cable structure and the complex distribution of the spatial magnetic field, it was challenging to characterize the internal corrosion area. Moreover, the rapid characterization of the corrosion position and its distribution area was the prerequisite to improving the corrosion degree diagnosis accuracy. By using the electrochemical method and COMSOL Multiphysics software, the experimental test and the finite element simulation of corroded steel cable bundles based on the metal magnetic memory were carried out. The dimensionless analysis parameter of magnetic characterization λ was constructed. The correlation between the φ–λ distribution curve and the circumferential central position φ_c was clarified. The linear growth trend between the variation amplitude Δλ of the φ–λ curve and the corrosion ratio α was revealed, and the growth slope K₁ was obtained. By linear fitting function, the characterization curves of K₁ and the circumferential angle of corrosion area Δφ were obtained. The goodness of fit R² reached 0.98. Finally, the characterization method of the corrosion circumferential distribution area (φ₁, φ₂) was proposed.