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Evaluation of Void Content in Carbon Fiber/Epoxy Composites Manufactured by Different Manufacturing Process

제작공법을 달리한 탄소섬유/에폭시 복합재의 기공함유율 평가 기법

  • Yoona, Sungho (Department of Mechanical Engineering, Kumoh National Institute of Technology) ;
  • Jang, Jungkeun (Department of Mechanical Engineering, Kumoh National Institute of Technology)
  • Received : 2016.12.03
  • Accepted : 2017.03.08
  • Published : 2017.04.01

Abstract

In this study, the procedures for quantitative measurement of void contents of carbon fiber/epoxy composites were suggested. Two types of the composites were considered: autoclave cured composite and filament wound composite. Void contents of the composites were evaluated by the density of the composites and their constituents, which was determined from weights in the air and water, and the weight fraction and volume fraction of the constituents obtained from the digestion method and combustion method. The surfaces of filtered carbon fibers were examined by FE-SEM in order to investigate the validity of resin removal from the composites. According to the results, the resin in the composites could be fully removed by the digestion method and combustion method. Therefore, the weight fraction and volume fraction of the constituents, and void content of the composites could be quantitatively obtained by the suggested procedures.

탄소섬유/에폭시 복합재의 기공함유율을 정량적으로 평가하기 위한 절차를 제시하였다. 고려한 복합재는 두 종류이며 오토클레이브 공법과 필라멘트와인딩 공법에 의해 제작하였다. 탄소섬유/에폭시 복합재의 기공함유율은 공기 중에서와 물 속에서의 무게에서 구한 복합재의 밀도와 구성재의 밀도, 그리고 산처리법과 고온연소법을 적용하여 구한 무게함유율과 부피함유율을 이용하여 평가하였다. 또한 FE-SEM을 통해 탄소섬유 표면을 관찰하여 복합재 내의 수지 제거 여부도 조사하였다. 연구결과에 따르면 복합재 내의 수지는 산처리법이나 고온연소법을 적용하면 충분히 제거할 수 있으며 구성재의 무게함유율과 부피함유율 그리고 복합재의 기공함유율은 본 연구에서 제시된 절차를 적용하면 정량적으로 평가할 수 있다.

Keywords

References

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