Analysis of Low Velocity Impact Damage and Compressive Strength After Impact for Laminated Composites

복합재 구조물의 저속 충격 손상 및 충격 후 압축 강도 해석

  • 서영욱 (한국항공우주연구원 공력구조팀) ;
  • 우경식 (충북대학교) ;
  • 최익현 (한국항공우주연구원 공력구조팀) ;
  • 김근택 (한국항공우주연구원 공력구조팀) ;
  • 안석민 (한국항공우주연구원 항공기술실)
  • 투고 : 2011.05.02
  • 심사 : 2011.07.01
  • 발행 : 2011.07.01

초록

The demand for weight saving and high performance of aircraft require the more uses of composite materials. However the complicate behaviors and various failure characteristics restrict usage of composite materials. Low-velocity impact damage is a major concern in the design of structures made of composite materials, because impact damage is hidden and cannot be detected by visual inspection. Especially, the reduction on compressive strength after impact is influenced by the ply delaminations introduced as damage by impact event. In this research, the numerical analysis was performed to investigate impact damage and compressive strength after impact. It was found that impact force history and compressive strength after impact calculated by the numerical analysis were compared and shown a good agreement with experimental results.

최근 항공기의 성능향상 및 경량화 등의 필요에 의해 많은 항공기 특히 소형항공기 구조물에 있어 복합재료의 사용이 증가되고 있다. 그러나 복합재료의 복잡한 기계적 거동 특성 및 파손양상 등으로 인하여 그 사용에는 많은 제한이 따르고 있는 실정이다. 복합재에 발생하는 저속충격은 외관상 드러나지는 않기 때문에 복합재 구조물을 설계하는 데 있어 매우 중요하며, 특히 충격 후 충격손상으로 야기되는 층간 분리등은 구조물의 압축강도를 현저하게 저하시킬 수 있다. 본 연구에서는 적층복합재 구조물의 저속충격에 의한 손상거동 및 충격 후 잔류압축강도를 수치적으로 예측하였다. 예측 된 충격하중 이력곡선과 충격후의 압축 강도를 시험결과와 비교하였고 잘 일치함을 확인 할 수 있었다.

키워드

참고문헌

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