Reconstruction of Stress Corrosion Cracks Based on Pulsed Eddy Current Signals

Abstract

Reconstruction of Stress Corrosion Cracks (SCCs) using conventional Eddy Current Testing method (ECT) shows its limitation especially when dealing with deep SCCs. Recently, a new approach utilizing Pulsed Eddy Current Testing (PECT) signals has been proposed to reconstruct wall thinning defect based on a deterministic optimization method. It is because PECT is found advantageous over the conventional ECT due to its features of abundant frequency components and large exciting currents. In this study, stochastic optimization methods of neural network, tabu search, simulated annealing and genetic algorithm are introduced to reconstruct the SCC profile from the PECT signals. The efficiency and accuracy of these stochastic methods are evaluated and discussed.