Tensile Strength of Composite Laminate Repaired Using Heat-blanket and a Novel Pressurization System

히트블랑켓과 새롭게 개발된 가압장치를 이용해 수리한 복합재 적층판의 인장강도 연구

  • Chae, Song-Su (School of Mechanical and Aerospace Engineering, Gyeongsang National University) ;
  • Lee, Gwang-Eun (School of Mechanical and Aerospace Engineering, Gyeongsang National University) ;
  • Ahn, Hyonsu (ANH Structure, Co., Ltd.) ;
  • Choi, Jin-Ho (School of Mechanical and Aerospace Engineering, Gyeongsang National University) ;
  • Kweon, Jin-Hwe (School of Mechanical and Aerospace Engineering, Gyeongsang National University)
  • Received : 2017.12.20
  • Accepted : 2018.02.06
  • Published : 2018.02.28


In the case of a conventional composite patch repair using a heat blanket, the adhesive is pressurized using only a vacuum bag. In this study, however, a pressurization system has been developed to apply additional air pressure on the vacuum bag. In order to verify the performance of the developed system, the composite laminates were repaired with scarf patches and then tested under tensile load to be compared with the strength of the defect-free laminate. Tensile tests were also conducted on specimens with the same configuration but bonded in an autoclave. As a result of the test, the tensile strengths of the specimens repaired using the heat blanket with vacuum only without external pressure, the specimens repaired with additional pressure by the developed system, and the specimens repaired with the same external pressure in an autoclave, showed the strength recovery ratios of 74.9, 81.0, and 78.2%, respectively. The results of the tensile test after moisture saturation and the dried fatigue test also showed that the strength recovery ratios of the specimens repaired under the external pressure of 1 atm using the developed system are slightly higher than that of specimens bonded in autoclave.


Supported by : 산업기술평가관리원(KEIT), 한국연구재단


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