Abstract:Capacitiveeddy current dual modality integrated nondestructive testing method combines the advantages of capacitive inspection technique in the inspection of insulators and eddy current inspection technique in the inspection of conductors, and can fulfill the overall inspection requirement of“insulatorconductor” hybrid structures suchasglass fiber compositerepairstructure.The principles ofthecapacitivemodeand eddy current modeofdual modalityintegratedinspectiontechniqueareanalysed, respectively,theinfluential factors of the inspection performance for dual modality integrated probe are identified. The influences of excitation signal frequency, liftoff distance, probe scan direction and coil design parameters on the inspection performance are studied in experiment. Normalized variation ratio (NVR) at the center of the target defect in the inspection characteristic signal variation ratio curve is taken as a quantitative indicator to intuitively characterize the influential pattern and degree of various factors on the inspection performance. The results indicate that experiment conditions and design parameters have different influential patterns on the inspection performance, among which the liftoff distance and coil parameters have obvious influence. Comprehensive considering the influential patterns of various factors may hopefully achieve the inspection performance improvement and guide the optimal probe design.