Crack Locating in High Conductivity Plate Based on Planar Array PECT

Pulsed eddy current testing (PECT) is widely studied for its rich spectrum information which can detect deeper defects than traditional single frequency eddy current testing (ECT) by the scanning of one eddy current probe. Based on the frequency domain characteristics analysis of pulsed excitation signal the superposition principle of magnetic field, the PECT differential response signals in time domain are verified to be synthesized by single frequency response signals of pulse harmonic components. The planar array PECT is proposed to locate the penetrating crack defect. With one coil excited and other coils detected, the crack defects are initially located by the peak value features of the PECT differential response signals. The accuracy of locating the defect by planar array PECT needs to be improved in the future. This study provides a way for solving pulsed responses in frequency domain in terms of the hard convergence of time domain in simulation of PECT and helps to develop the crack defect locating by planar array PECT.