한국추진공학회지 (Journal of the Korean Society of Propulsion Engineers)

  • 제17권2호
  • /
  • Pages.31-38
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  • 2013
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  • 1226-6027(pISSN)
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  • 2288-4548(eISSN)
한국추진공학회 (The Korean Society of Propulsion Engineers)
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열습환경을 고려한 핀 체결부 복합재 파괴거동

Failure Behavior of Pin-jointed Composites under Hygrothermal Environments

  • 김찬규 (금오공과대학교 대학원 기계공학과) ;
  • 황영은 (금오공과대학교 대학원 기계공학과) ;
  • 윤성호 (금오공과대학교 기계공학과)
  • 투고 : 2013.01.28
  • 심사 : 2013.03.08
  • 발행 : 2013.04.01
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초록

본 연구에서는 열습환경에 노출된 탄소섬유/에폭시 복합재의 핀 체결부에 대해 핀 하중시험을 수행하고 수집된 음향방출신호를 분석하여 열습환경이 복합재 핀 체결부의 파괴거동에 미치는 영향을 조사하였다. 이때 시편은 환경조건에 노출되기 전의 시편(Base), 상온침수환경에 노출된 시편(RT), 고온침수 환경에 노출된 시편(HT)으로 구분하였다. 연구결과에 의하면 RT 시편과 HT 시편의 베어링 강도는 Base 시편에 비해 각각 2.2%와 13% 감소하였다. 음향방출신호의 경우 시편 종류에 따라 파손이 가속화되는 시점이 달라짐을 나타내었으며 RT 시편과 HT 시편은 Base 시편에 비해 모재균열에 의한 이벤트가 감소하는 경향이 나타났다. 이로 미루어 판단하면 열습환경은 복합재 핀 체결부의 음향방출신호뿐 아니라 계면특성의 저하도 초래함을 알 수 있었다.

This research analyzed the acoustic emission signals collected from the pin loading tests and investigated the effect of hygrothermal exposure on the fracture behavior of the pin-jointed carbon fiber/epoxy composites. The composite specimens include: the Base specimen that has not been exposed to any environments, the RT specimen that has been immersed in room temperature water, and the HT specimen that has been immersed in high temperature water. According to the pin loading test, the RT and the HT specimens showed 2.2% and 13% decreases in the bearing strength compared to the Base specimen, respectively. The analysis of the acoustic emission signals showed different fracture acceleration points for three types of the specimens. Furthermore, for the RT and the HT specimens, the event from the matrix crack signals in the composites decreased. This shows the effect of the hygrothermal conditions on the acoustic emission signals. Additionally, upon investigating the fracture behaviors of the pin-jointed composites, the exposing specimens to hygrothermal environments decreases the interfacial characteristics of the composites.

키워드

참고문헌

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