Characterization of laminated structure on scarfed slope of CFRP by utilizing eddy current testing with differential type probe

Laminated structure (fiber orientation and boundary of adjacent layers) on scarfed surface of CFRP is characterized by eddy current testing (ECT) with differential type probe. The fiber orientation of each layer is identified by C-scanning of ECT. The peak of eddy current signal amplitude on each layer, which is shifted toward the upper side layer due to the distribution of eddy current, indicates the boundary of the adjacent layers. Because the peak of the eddy current signal is well represented by electromagnetic numerical simulation of finite element analysis, the boundary of the adjacent layers is correctly identified by combining ECT and numerical analysis. These abilities of ECT are useful for automation of scarf adhesive repair process.