Detection of Cracks under Cover and Corrosion using UHF Probe

Detection of cracks under cover poses a significant challenge to several non-destructive testing (NDT) techniques. In microwave NDT, detection of cracks is largely dependent on crack orientation and dimensions, type of dielectric cover, and its overall thickness. In this paper, we demonstrate the imaging capability of a UHF probe towards crack detection under cover and corroded metal. The ability of the probe to detect cracks under cover with different materials and thicknesses is highlighted through the high contrast images produced by the probe. Furthermore, the images of the crack under different covers are benchmarked to a Ka-band rectangular aperture probe image. Additionally, images of a crack under corrosion rendered by the probe are also included to emphasize the potential of the probe to produce high-quality images of practically relevant samples at a much lower frequency.