Crack visualization of metallic structures using time-domain reflectometry with two-dimensional microstrip lines

The present study investigated crack visualization in metallic structures using time-domain reflectometry with a two-dimensional microstrip line. 2D inspection was enabled by covering the inspected structure surface with the microstrip conductor to compensate for the lack of information in the transverse direction. The experimental results demonstrated that crack propagation could be clearly visualized. However, false cracks appeared at the same position regardless of the crack position. The electromagnetic field simulation results clarified that the false cracks observed in the experiments were caused by cross talk. The problem can be eliminated by arranging the microstrip conductor appropriately.