Application of finite element eddy current analysis to nondestructive detection of flaws in metallic structures

The finite element method was used in the development of a model for impedance calculations of test coils used in nondestructive testing (NDT). The procedure was applied in characterization of various rectangular slab materials. Also, applications to the characterization of discontinuities (flaws) of open channel shape in metallic slabs was included in the work. Coil impedances as affected by slab thicknesses were obtained for purposes of uniformity and quality control and assurance testing of metallic parts, were obtained. These results and modeling techniques are shown to enable one to maximize coil sensitivities to given tasks in NDT. Equipotential plots are used throughout for illustration purposes.