Simulation of Crack Defects Testing Around Holes in Multi-layer Metal Riveting Structures Based on Pulsed Eddy Current

Pulsed eddy current (PEC) testing technology, renowned for its deep defect detection capability and high sensitivity, has been applied in the detection of internal defects in multi-layer riveted structures. To reveal the influence of the size parameters of PEC rectangular sensors on the detection performance of crack defects around holes in these structures, a three-dimensional simulation model of PEC rectangular sensor was constructed using the finite element simulation software COMSOL. Based on the distribution law of PEC in multi-layer riveted structures, the impact of probe structure parameters and central axis offset on the detection effect was studied through numerical simulation. The simulation test results show that the detection sensitivity of the rectangular probe peaks when the ratio of length to width to height is 1:1.25:1.25, which is suitable for detecting cracks around holes in multi-layer riveting structures. Furthermore, it was found that to ensure adequate detection sensitivity, the offset should lower than 1 mm in the direction perpendicular to the crack defect, and less than 0.2 mm in the direction parallel and overlapping with the defect. The findings provide a foundational basis for the design of sensor size parameter aimed at detecting cracks around holes in multi-layer metal riveting structures.