Study of Dual Excitation Coil Sensitivity for Defects Detection on Carbon Steel Plates

In some industrial applications, weld defects of carbon steel plates have always ranked among the difficult problems in eddy current inspection. For this reason, and in order to analyze the sensitivity of eddy current probes and their ability to detect small cracks, a uniform dual excitation eddy current probe, consisting of two excitation coils and one detection coil has been investigated. Such investigation was based on the calculation and analysis of the response signals recovered by the receiving coil which provide information on the degree and size of the cracks. During our study, we will address the influence of crack length and width on the amplitude and quality of the sensor response signals. To solve the equations governing the electromagnetic problem treated, a 3D numerical simulation based on the finite element (FE) method has been established using COMSOL Multiphysics software.