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THz 전자기파를 이용한 나노시멘트 광학물성 측정

Measurement of Optical Properties of Nano-Cement Using THz Electromagnetic Waves

  • 김헌영 (한국철도기술연구원 첨단소재연구팀) ;
  • 강동훈 (한국철도기술연구원 첨단소재연구팀) ;
  • 오승재 (연의-생공연 메디컬융합 연구소) ;
  • 주철민 (연세대학교 기계공학과)
  • 투고 : 2016.07.01
  • 심사 : 2016.09.07
  • 발행 : 2016.10.30

초록

탄소나노튜브와 그래핀 등으로 대표되는 탄소 동소체기반 나노재료의 우수한 기계적 특성을 이용해 콘크리트의 압축강도를 증가시키기 위한 연구가 활발히 진행되고 있다. 일반적으로, 나노재료 적용을 통한 강도 향상을 위해서는 콘크리트 내 나노재료의 분산성이 높아야 하며, 이를 검증하기 위해 외부에서 비파괴적으로 확인할 수 있는 검사 기술이 요구된다. 본 연구에서는, 적외선의 직진성과 마이크로파의 투과성을 동시에 갖고 있는 THz 전자기파를 이용하여 MWCNT 및 GO가 포함된 두 종류의 나노시멘트 모르타르 시편을 제작하여 굴절률 및 흡수율과 같은 기초 광학물성 측정 시험을 수행하였다. 시험을 통해 일반 시멘트 모르타르에 비해 나노재료가 포함된 시편에서 굴절률은 평균 1.0~2.5%, 흡수율은 평균 -14~28% 차이로 측정됨을 확인하였다. 이를 통해, 비파괴적으로 콘크리트 내부에 포함된 나노재료의 분포도를 영상화할 수 있는 기술의 실현 가능성을 확인하였다.

Enhancing mechanical strength of concrete has been fascinated using carbon-based nanomaterials such as CNT and graphene. The key to improving strength is a dispersion of nanomaterials. A novel method is required to investigate the dispersion inner concrete nondestructively. In this study, the optical optical properties such as refractive index and absorption coefficient are measured in nano-cement mortar specimens containing MWCNT and GO using THz electro-magnetic waves. From the results, the properties of nano-cement mortar are confirmed to be 1.0% to 2.5% higher in refractive index, and -14% to 28% higher in absorption coefficient than those of cement mortar at the average values. Using these characteristics, visualizing the dispersion of nano-concrete structures seems possible in future.

키워드

참고문헌

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