포토믹서 테라헤르츠 기술 기반의 영상화 시스템을 통한 유리섬유 복합재료 결함의 비파괴검사법 = Non-destructive Evaluation of Defects of Glass fiber Composites using Imaging System based on Photo-mixer Terahertz Technique

다국어 초록 (Multilingual Abstract)

In this study, non-destructive evaluation using photo-mixer terahertz technique was studied to visualize the hidden damage in composite structures. A terahertz wave system was developed based on photo-mixer to detect the internal defects of the composite structure, and foreign material was simulated in a glass fiber-reinforced plastic (GFRP) specimen using PET film coated with silver nano-wire. For the visualization, an imaging algorithm for terahertz signal processing and stage control was developed using a GUI based on LABVIEW. The inspection was performed using the developed continuous terahertz inspection system and the terahertz waveform acquired in the single frequency was used to visualize defects.

국문 초록 (Abstract)

본 논문에서는 포토믹서 테라헤르츠 기술 기반의 영상화 시스템을 이용하여 유리섬유 복합재료의 결함을 영상화하기 위한 비파괴검사 기술에 대한 연구를 진행하였다. 유리섬유 복합재료 구조물의 내부 결함을 검사하기 위해 photomixer 기반의 테라헤르츠 발생 시스템을 이용하였고, 복합재 제작 공정 중에 시편 내부로 들어갈 수 있는 이물질을 모사하기 위해 유리섬유복합재료(GFRP) 시편 내부에 은 나노와이어가 입혀진 PET 필름을 사용하여 모사하였다. 내부 결함의 영상화를 위해 테라헤르츠 신호의 처리와 stage 제어를 위한 영상화 알고리즘을 Labview 기반의 GUI를 통해 개발하였다. 제작된 포토믹서 테라헤르츠 검사 시스템을 사용하여 결함 검사를 수행하였고, 단일 주파수를 이용해 취득한 테라헤르츠 파형을 영상화 하였다.

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