Three-dimensional finite element computation of electromagnetics for nondestructive testing

The remote field eddy current (RFEC) nondestructive testing (NDT) is a newly-developed technique for pipe inspection, especially for ferromagnetic material such as a steel pipe, for it has the distinct advantage of the same sensitivity for both inside pipe and outside pipe defects, which is quite different from traditional eddy current NDT. In spite of great efforts, there are still some unclear issues in the underlying physics of RFEC phenomena, because most of the researchers resorted to two-dimensional numerical model and it is not suitable for the industrial case. A three-dimensional finite element (FE) computation of electromagnetics (EM) for the RFEC has been researched, where the hybrid potentials model is proposed and a substructure-front technique is employed successfully to analyze the 3D EM field of NDT problems. Results validating the approach and showing the versatility are presented and are also used to explain some phenomena in RFEC NDT.