Detectability evaluation of eddy current testing probes for inspection of defects in carbon fiber reinforced polymer laminates

With the growing interest to use composite materials in industrial fields such as the aerospace and the transportation engineering, more attention is devoted to the development and application of non-destructive testing (NDT) techniques to the inspection of defects in carbon fiber reinforced polymer (CFRP). High frequency eddy current testing method is considered to be a promising tool for the NDT of CRFP. In this work, an anisotropic numerical code based on Ar formulation is developed and validated at first. The detectability of four different types of ECT probes is then evaluated by using the developed numerical code for detecting the crack type defects in CFRP laminates. Furthermore, the S/N ratios of the four probes related to the inclination noise are calculated numerically and compared to evaluate the detectability of these ECT probes. As conclusion, the newly proposed dual function vertical coil probe is found most suitable for the CFRP fiber breakage detection.