Multidirectional Alternating Current Potential Drop Technique for Detecting Random Cracks

The alternating current potential drop technique has been widely used to measure subsurface cracks in metal structures. However, the application of the technique to random cracks has, to date, been limited. By using a multidirectional alternating current potential drop technique, the angle between crack and exciting electrode wire changes from 0° – 90° to 67.5° – 90°, which considerably expanded the ranges of detection. Simulation and experiment results showed that this technique can accurately measure the depth of random cracks.