Journal of the Korean Society of Safety (한국안전학회지)

The Korean Society of Safety (한국안전학회)
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A Study of Mode II Interlaminar Fracture for CFRP Laminate Composite using the 4-point Bending CNF Specimen

4점굽힘 CNF 시험편을 이용한 CFRP적층 복합재 모드 II 층간파괴

  • Kwon, Oh-Heon (Division of Safety Engineering, Pukyong National University) ;
  • Kang, Ji-Woong (Division of Safety Engineering, Pukyong National University) ;
  • Tae, Hwan-Jun (Division of Safety Engineering, Pukyong National University) ;
  • Hwang, Yeong-Yeun (Department of Control and Instrumentation Engineering, Pukyong National University) ;
  • Yun, Yu-Seung (Department of Occupational Health and Safety Engineering, Inje University)
  • 권오현 (부경대학교 안전공학부) ;
  • 강지웅 (부경대학교 안전공학부) ;
  • 태환준 (부경대학교 안전공학부) ;
  • 황용연 (부경대학교 제어계측공학과) ;
  • 윤유성 (인제대학교 보건안전공학과)
  • Received : 2010.03.26
  • Accepted : 2010.06.02
  • Published : 2010.06.30
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Abstract

Unidirectional Carbon Fiber Reinforced Plastics (CFRP) are advanced materials which combine the characteristics of the light weight, high stiffness and strength. For those reasons, the use of the unidirectional CFRP has increased in jet fighters, aerospace structures. However, unidirectional CFRP composites have a lot of problems, especially delamination, compared with traditional materials such as steels and aluminums, and so forth. Therefore, the interlaminar fracture toughness for a laminate CFRP composite is very important. In this study, The mode II interlaminar fracture toughness was measured by using center notched flexure(CNF) test specimen. The CNF specimens using unidirectional carbon prepreg were fabricated by a hot-press with the gage pressure and temperature controller. And three kinds of a/L ratio was applied to these specimens. Here, we discuss the relations of the crack growth and the mode II interlaminar fracture under the four point bending CNF test. From the results, we shows that mode II interlaminar was occurred when the more $a_0$/L ratio, the less load. And $G_{IIC}$ also were obtained as 5.33, 2.9 and $0.58kJ/m^2$ according to $a_0$/L ratio=0.2, 0.3 and 0.4.

Keywords

Acknowledgement

Supported by : 부경대학교

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