Quantitative Detection and Scanning Imaging of Corrosion Defects

Quantitative detection of the length of corrosion defects, using the zero-crossing time of the transient induced voltage signal to quantitatively detect the depth of corrosion defects, using the peak value of the transient induced voltage signal to quantitatively detect the corrosion defect volume. In the center of the bottom of the excitation coil, the eddy current array coils of eight detection coils are symmetrically arranged in accordance with the flow direction of the current.

When the simulated corrosion defect sample is processed, the two detection coils at the symmetrical position receive the maximum eddy current response signal. There is a rule between the peak ratios: for different corrosion depths, when the probe array is completely corroded, the ratio is greater than or equal to 0.5; when the probe array is not completely corroded, the ratio is less than or equal to 0. 2. Therefore, this ratio can be used as a characteristic parameter to determine whether the detection coil has been etched for a probe that has not been corroded. When a corrupted image is displayed, the path it passes through will not be displayed. This effectively eliminates image distortion.