The effect of eddy current probe configurations on crack signal magnitude: Consideration of excitation coil direction

The configuration of an eddy current (EC) probe is a critical factor that has consistently drawn the attention of researchers during the development of EC probes. This is because the configuration directly impacts the magnitude and distribution of the ECs generated on the test specimen, which, in turn, determines the ability to detect defects in the sample. In this study, we have considered three EC probe configurations with similar excitation and detection coil dimensions that have been oriented pancake and tangential to the test specimen surface. Our primary aim was to evaluate the ECs generated on the test specimen and the output crack signal magnitude. To achieve this, we employed finite element analysis to compare and evaluate the efficiency of EC generation on its surface across the three configurations. We then conducted experiments using the three EC probes to validate the simulation results and evaluate the effectiveness of detecting four artificial cracks on an aluminum plate.