Title: Signal-Distribution-Based Crack Detection for Divertor Monoblock Inspection using Eddy Current Testing
Abstract: This study evaluated the applicability of eddy current testing to the surface inspection of a divertor plasma-facing unit in a Tokamak fusion reactor. Artificial slits were introduced on the surfaces of some samples. The eddy current testing was performed to detect these slits. A quantitative detection evaluation method based on evaluating the distribution differences is proposed. The results reveal that the signals of slits near the edge are easily buried by the edge signals and difficult to detect directly from the signal amplitude image. With the aid of the proposed method, not only the slit in the middle of the sample surface but also the slits near the sample edges were successfully detected by eddy current testing.