Fig 1.
Schematic diagram of eddy current detection.
Fig 2.
Equivalent circuit diagram.
Fig 3.
Equivalent model of variable parameter defect detection system for cylindrical hole defects (at the axial section).
Table 1.
Material parameters.
Table 2.
Key parameter settings for eddy current testing simulation models.
Fig 4.
Schematic diagram of mesh partitioning.
Fig 5.
Magnetic induction intensity energy distribution diagram on the shaft surface.
Fig 6.
Magnetic induction intensity distribution curve of the horizontal shaft surface.
Fig 7.
Curve diagram of magnetic induction intensity distribution on the vertical shaft surface.
Fig 8.
Magnetic field variation curves for 6 cylindrical hole defects with different bottom diameters:
(a) HMII variation curve, (b) VMII variation curve, (c) PHMII variation curve, (d) PV MII variation curve.
Fig 9.
Magnetic field variation curves at different depths of cylindrical hole defects:
(a) HMII variation curve, (b) VMII variation curve, (c) PHMII variation curve, (d) PVMII variation curve.
Fig 10.
The shaft to be tested has different surface defects: (a) Cylindrical holes of different diameters; (b) Cylindrical holes of different depths.
Fig 11.
Eddy current testing experimental platform.
Fig 12.
Simulation and experimental comparison results of coil voltage signals under different cylindrical hole bottom diameters: (a) Bottom diameter is 1 mm; (b) Bottom diameter is 2 mm; (c) Bottom diameter is 4 mm; (d) Bottom diameter is 6 mm.
Fig 13.
Simulation and experimental comparison results of coil voltage signals at different cylindrical hole depths: (a) Depth is 1 mm; (b) Depth is 2 mm; (c) Depth is 3 mm; (d) Depth is 6 mm.