Electromagnetic nondestructive testing of rust region in steel

The inspection of rust region in steel is important in the petrochemical plant, etc. The B--H curve and the conductivity of rust region in steel are different from those of the normal steel. Then, the detection of rust region in steel is possible by detecting the difference of those electromagnetic properties using an inspection method. In this paper, those electromagnetic properties of the rust region in steel are measured utilizing three-dimensional (3-D) axis-symmetric finite-element method (FEM) and experiment. The electromagnetic inspection technique of the rust region is examined using 3-D edge-based hexahedral nonlinear FEM. The possibility of detecting the rust region using the proposed inspection system is illustrated. In addition, the experimental verification is also carried out.