An investigation into the potential of microwave NDT for structural materials

The potential of using EM wave technology within the microwave region (300MHz-300GHz) to detect defects in sheet metals, such as those used in vehicle platforms, is investigated. The proposed EM wave NDT system will be integrated into a wide variety of structural elements (e.g. automotive and construction) and will provide continuous real-time structural health monitoring of the materials. The system will be able to provide information related to the presence, type and location of damage or defects. Two sensors are studied for defect detection and monitoring, a rectangular patch structure and an interdigitated electrode structure. Initial experimental results demonstrate that the presence of defects such as cracks near the surface of the sensor elicit a change in sensor response. Detailed experimental set-up and preliminary measurement results are presented.