Monitoring of military-designated composites and processing of the images obtained with the use of terahertz radiation

Abstract

With regards to composites, the need for non-destructive evaluation (NDE) of their inner structure, or constructions they form continuously rises. Nowadays, a great deal of attention has been paid to methods based on the use of Terahertz radiation (THz). It is related to the exceptional properties of THz radiation which allows for contactless, safe, and fast inspection of non-conductive materials. In the frame of this work the results of the use of the Terahertz imaging method, operated at the frequency of 300 GHz, are presented. The selected aramid fiber-reinforced composites with intentionally introduced defects were monitored. A thorough structural materials inspection was carried out in transmission mode. The obtained images were preprocessed and enhanced. Overall, the phenomenon of noninvasive monitoring using Terahertz radiation and the tremendous advances in this field were presented.