Spoof Plasmon Polaritons for NDE Applications an Experimental Demonstration
NASA is exploring the use of microwave spoof plasmon polaritons to detect defects in metallic structures. This work investigates the detection of simulated defects in the form of aluminum wires as small as 1.6 mm diameter and 2mm long that are placed in a grooved aluminum test article. The inclusions simulate manufacturing defects, and the sum of the delta impedance is shown to increase with increasing volume of added metal. A threshold value of 50Ω has been proposed for defect detection. In addition to detecting defects, the technique also estimates the volume of the defect.