Research on star-shaped coil probe in eddy current testing of aluminum plate

Abstract

To detect defects from different angles and overcome the potential omission issues of traditional eddy current probes, this paper proposes a star-shaped eddy current probe composed of four coils based on defect decomposition theory. The probe is optimized to enhance sensitivity and reliability in detecting defects from various directions. A 3D model of the star-shaped probe is constructed in finite element software to simulate the detection of surface defects at different angles (including 90°, 120°, 135°, and 150°). Through simulation analysis, the distribution of the probe's position and magnetic flux density on the sample surface when the defect signal amplitude reaches its maximum along the scanning path, as well as the variation of detection coil voltage with defect length, are studied. Finally, an experimental system is established to verify the performance of the star-shaped coil probe in detecting defects of different angles and lengths near the scanning path, further proving the effectiveness and reliability of the probe in multi-angle defect detection. Under the same detection conditions, the detection signal of star shaped probe is significantly improved. Moreover, the proposed star—shaped probe shows great potential in practical applications due to its enhanced multi—angle defect detection ability.