Rotating uniform eddy current probe using four rectangular excitation coils with ferrite cores for cracks detection in conductive materials

In this study, we introduce a new rotating uniform eddy current (RUEC) probe designed to identify artificial cracks in conductive materials. The RUEC probe comprises four rectangular coils, divided into two sets of diagonally positioned coils. By providing two alternating current sources with a 90° phase difference to the two sets of coils, a RUEC distribution with uniform amplitude in all directions can be produced on the surface of the test specimen. Furthermore, ferrite cores are integrated into the four coils to enhance the crack detection ability. To confirm that the RUEC probe model produces RUECs with uniform amplitude in all directions on the test specimen surface, we conducted finite element method (FEM) simulations. We then conducted experiments with the RUEC probe to identify artificial cracks of varying sizes on the test specimen. The experimental results demonstrate that the RUEC distribution on the test specimen surface enabled successful detection of cracks in all directions with the probe.