Journal of the Korean Recycled Construction Resources Institute (한국건설순환자원학회논문집)

Korean Recycled Construction Resources Institute (한국건설순환자원학회)
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Importance of Impregnation and Polishing for Backscattered Electron Image Analysis for Cementitious Self-Healing Specimen

시멘트계 자기치유 시편에 대한 반사전자현미경 이미지 분석을 위한 함침과 연마의 중요성

  • Kim, Dong-Hyun (Materials Science and Engineering, Kunsan National University) ;
  • Kang, Kook-Hee (Materials Science and Engineering, Kunsan National University) ;
  • Bae, Seung-Muk (Center For Research Facilities, Kunsan National University) ;
  • Lim, Young-Jin (Materials Science and Engineering, Kunsan National University) ;
  • Lee, Seung-Heun (Materials Science and Engineering, Kunsan National University)
  • 김동현 (군산대학교 신소재공학과) ;
  • 강국희 (군산대학교 신소재공학과) ;
  • 배승묵 (군산대학교 공동실험실습관) ;
  • 임영진 (군산대학교 신소재공학과) ;
  • 이승헌 (군산대학교 신소재공학과)
  • Received : 2017.09.28
  • Accepted : 2017.11.15
  • Published : 2017.12.30
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Abstract

Studies on self-healing have currently been diversified and the methods to evaluate the studies have become more diversified as well. Among them, the back-scattered electron (BSE) image acquired through the scanning electron microscope (SEM) is attempted as the means to evaluate the self-healing effect on cracks. In order evaluate by the BSE image, sophisticated pre-processing of specimen is critical and this injected inside the particle, pore and artificial crack of the hardener to stabilize the structure of the newly generated self-healing product and it enables to endure the stress on polishing without deformation. The impregnated specimen smoothen the surface to obtain the BSE image of high resolution that polishing is made for diamond suspension for wet polishing after dry polishing. As a result of evaluating the self-healing product on the impregnated and polished self-healing specimen, the generated product is formed from the surface of the artificial crack and the self-healing substances are confirmed as $Ca(OH)_2$ and C-S-H.

자기치유에 관한 연구는 현재 다각화되었으며 연구를 평가하는 방법도 다양해졌다. 그중에서, 스캐닝 전자 현미경(SEM)을 통해 획득된 반사전자(BSE) 이미지는 균열에서의 자기치유 효과를 평가하는 수단으로 시도되었다. BSE 이미지를 평가하기 위해서 정교한 시편 전처리가 대단히 중요하다. 에폭시 함침은 경화체의 입자, 기공과 인공 균열 내부에 투입되어 새롭게 생성된 자기치유 수화물의 구조를 안정화시키고 변형 없이 연삭 및 연마의 응력을 견딜 수 있게 한다. 함침 시편은 표면을 매끄럽게 하고 고해상도의 BSE 영상을 얻기 위해 건조 연마 후 습식 연마용 다이아몬드 서스펜션으로 연마한다. 함침과 연마가 된 자기치유 시편의 자기치유 수화물을 평가한 결과, 생성된 수화물은 인공균열의 표면에 형성되었으며 자기치유 물질은 $Ca(OH)_2$와 C-S-H로 확인되었다.

Keywords

References

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