The evolution of the non-destructive defect detection in composites with the use of terahertz radiation

Abstract

The unique properties of Terahertz (THz) radiation include among others the ability to penetrate through electrical insulators such as ceramics, plastics, or plastic composites. Because of that, it is possible to non-destructively and contact free analyze the materials with internal cavities both in transmission and reflection configuration. The commercially available low-power sources provide results which quality is still beyond expectations. As a result, efforts are being made to resolve the studies' focused on optimizing the experimental setup. In the presented work the comparison between two experimental setups operated at the frequencies of 100 GHz and 300 GHz was described. The studies were performed in transmission mode on selected composite material. They were next compared to the results obtained using common pulsed thermography. Some practical application in non-destructive testing and possible improvements of described methods are discussed.