적층수에 따른 GFRP 피막 Al 평활재의 저주기 피로수명 평가
Low Cycle Fatigue Life Behavior of GFRP Coated Aluminum Plates According to Layup Number
0
조회
0
다운로드
2
인용
0
참고문헌
키워드
초록
섬유 금속 적층판(Fiber metal hybrid laminate, FML)은 금속재료와 FRP의 접합으로 기존의 금속 소재가 가지지 못했던 뛰어난 물성과 가벼운 무게로 경제적인 구조용 재료로 사용된다. 그러나 섬유의 형태와 종류, 적층조건에 따라 물성의 차이가 크며, 파괴거동을 예측하기 어렵다는 단점이 있다. 본 논문에서는 Al6061-T6 합금에직조형태의 유리섬유 플라스틱(GFRP, GEP118)을 적층피막한 복합재의 파손거동에 대해 연구한다. Al합금에 GFRP 1, 3, 5 겹을 피막한 3가지 조건으로 성형하고, 피막의 적층수를 변수로 정적시험과 저주기 피로시험을 병행하여파손거동을 분석하였다. 저주기 피로시험에서는 변형률-수명 해석, 전변형률 에너지밀도법을 사용하여 분석하고, 피로수명을 예측하여 하이브리드 재료에 대한 수명예측성을 분석하였다. 인장해석 결과, GFRP 피막으로 인한 강화효과는 없었고, 피로시험시 나타나는 히스테리시스 형상은 GFRP피막 유무와 피막 수에 상관없이 모재인 Al합금의 거동을 따랐다. 저주기 피로시험 결과 GFRP의 피막으로 피로강도가 증가하였지만, GFRP의 두께에 따라 비례하여 증가하지는 않았다.
Abstract
Fiber metal hybrid laminate (FML) can be used as an economic material with superior mechanical properties and light weight than conventional metal by bonding of metal and FRP. However, there are disadvantages that it is difficult to predict fracture behavior because of the large difference in properties depending on the type of fiber and lamination conditions. In this paper, we study the failure behavior of hybrid materials with laminated glass fiber reinforced plastics (GFRP, GEP118, woven type) in Al6061-T6 alloy. The Al alloys were coated with GFRP 1, 3, and 5 layers, and fracture behavior was analyzed by using a static test and a low cycle fatigue test. In the low cycle fatigue test, strain - life analysis and the total strain energy density method were used to analyze and predict the fatigue life. The Al alloy did not have tensile properties strengthening effect due to the GFRP coating. The fatigue hysteresis geometry followed the behavior of the Al alloy, the base material, regardless of the GFRP coating and number of coatings. As a result of the low cycle fatigue test, the fatigue strength was increased by the coating of GFRP, but it did not increase proportionally with the number of GFRP layers.
참고문헌 (15)
- Lin, C.T, "Fatigue Behaviour of Carbon Fibre-reinforced Aluminium Laminates", Composites, 22(2), pp.135~141 (1991)
- Yoon, H.K, "A Study on Characterisitcs of Tensile Strength and Fatigue Life with Hybrid Composite Materials for Aircraft", Proceedings of the KSME 1995 Conferenc, pp.213~217 (1995)
- Vogelesang, L.B, "Development of Fibre Metal Laminates for Advanced Aerospace Structures", Journal of Materials Processing Technology, 103(1), pp.1~5 (2000)
- Cortes, P.W, "The Fracture Properties of a Fibre–metal Laminate Based on Mag-nesium Alloy", Composites Part B: Engineering, 37(2-3), pp.163~170 (2005)
- Kawai, M, "Effects of Rratio on the Off-axis Fatigue Behavior of Unidirectional Hybrid GFRP", Al Laminates at Room Tamperature, 2006, pp.28(10), 1226~1238
- Monfared, A, "CFRP Reinforcing to Extend the Fatigue Lives of Steel Structures", Fourth International Conference on FRP Composites in Civil Engineering(CICE2008), pp.1~6 (2008)
- 이환우, "접착 패칭된 박-후판 결합형 보강판의 피로균열성장 거동", 한국해양공학회지, 22(3), pp.89~95 (2008), 한국해양공학회
- Khan, S.U, "Post-stretching Induced Stress Redistribution in Fibre Metal Laminates for Increased Fatigue Crack Growth Resistance", Composites Science and Technology, 69(3-4), pp.396~405 (2009)
- Ergun, E, "Fatigue and Fracture Analysis of Aluminum Plate with Composite Patches under the Hygrothermal Effect", Composite Structures, 9(11), pp.2622~2631 (2010)
- 이성혁, "경량화 알루미늄-GFRP 혼성 사각관 보의 굽힘성능 및 붕괴 메커니즘", Composites Research, 20(3), pp.8~16 (2007), 한국복합재료학회
- Yoon, H.K, "A study on Fatigue Crack Retardation Using NDT Test in a Hybrid Composite Material Reinforced with a CFRP", Journal of the Korean Society for Composite Materials, 12(3), pp.1~7 (1999)
- Coffin, L.F, "A Study of the Effects of Cyclic Thermal Stress on a Ductile Metal", Trans. ASME, 76, pp.931~950 (1954)
- Halford, G.R, "The Energy Required for Fatigue", Journal of Materials, 1(1), pp.3~18 (1966)
- Ellyin, F, "An Energybased Fatigue Failure Criterion", Microstructure and Mechanical Behavior of Materials, 2, pp.541~600 (1985)
- Basquin, O.H, "The Experimental Law of Endurance Tests", American Society for Testing and Materials Proceedings, 10, pp.625~630 (1910)