Nondestructive Microfailure and Interfacial Evaluation of Plasma-Treated PBO and Kevlar Fibers/Epoxy Composites using Micromechanical Test and Acoustic Emission

Micromechanical 시험법과 음향방출을 이용한 플라즈마 처리된 PBO와 Kevlar 섬유강화 Epoxy 복합재료의 비파괴적 파단특성 및 계면물성 평가

  • 박종만 (경상대학교 응용화학공학부 고분자공학전공, 항공기부품기술연구센터) ;
  • 김대식 (경상대학교 응용화학공학부 고분자공학전공, 항공기부품기술연구센터) ;
  • 김성룡 (충주대학교 고분자공학과)
  • Published : 2003.08.01

Abstract

Comparison of interfacial properties and microfailure mechanisms of oxygen-plasma treated poly(p-phenylene-2,6-benzobisoxazole(PBO. Zylon) and poly(p-phenylene terephthalamide)(PPTA, Kevlar) fibers/ epoxy composites were investigated using micromechanical technique and nondestructive acoustic emission(AE). Interfacial shear strength(IFSS) and work of adhesion, Wa of PBO or Kevlar fibers/epoxy composites increased by oxygen-plasma treatment. Plasma-treated Kevlar fiber shooed the maximum critical surface tension and polar term, whereas the untreated PBO fiber showed the minimum value. Microfibril fracture pattern of plasma-treated Kevlar fiber appeared obviously. Based on the propagation of microfibril failure toward core region. the number of AE events for plasma-treated PBO and Kevlar fibers increased significantly. The results oi nondestructive AE were consistent well with microfailure modes by optical observation in microdroplet and two-fiber composites tests.

Micromechanical 시험법과 음향방출을 이용하여 산소 플라즈마 처리된 PBO와 Kevlar 섬유강화 에폭시 복합재료의 계면물성과 미세파괴메카니즘을 고찰하여 상호 비교하였다. 산소 플라즈마 처리된 PBO와 Kevlar 섬유강화 에폭시 복합재료의 계면전단강도와 접착일은 극성 작용기의 도입으로 향상 시킬 수 있었다. 임계표면장력과 총 표면자유에너지 중 극성 표면자유에너지는 플라즈마 처리된 Kevlar 섬유에서 가장 컸으며. 미처리된 PBO의 섬유의 경우에서 가장 작았다. Microfibril 파단 형상은 산소 플라즈마 처리된 Keviar 섬유의 경우에서는 명확하게 관찰 되었으며. 미처리와 비교차여 microfibril 파단이 대각선 방향으로 연속적해서 일어나 가장 많은 섬유 파단 신호가 감지되었다 비파괴 음향방출법을 이용하여 얻은 섬유파단 감지 결과는 microdroplet과 두 섬유강화 복합재료 시험법에서 광학현미경을 이용하여 관찰한 미세파단 형상과 상호 일치하였다.

Keywords

References

  1. Materials Letter v.44 Simple model for the temperature-dependent compressive strength polymer fibers Lacks,D.J. https://doi.org/10.1016/S0167-577X(99)00288-8
  2. Composite Science and Technology v.60 Effects of heat treatment on the mechanical preperties of Kevlar-29 fiber Yue,C.Y.;Sui,G.X.;Looi,H.C. https://doi.org/10.1016/S0266-3538(99)00137-2
  3. Composite Science and Technology v.60 The Effects of chemical treatment on reinforcement/matrix interaction on Kevlar-fiber/bismaleimide composites Lin,T.K.;Wu,S.J.;Lai,J.G.;Shyu,S.S. https://doi.org/10.1016/S0266-3538(00)00074-9
  4. Polymer v.37 Improved interfacial adhesion via chemical coupling of polybenzobisoxazole fiber-polymer systems Yalvac,S.;Jakubowski,J.J.;So,Y.H.;Sen,A. https://doi.org/10.1016/0032-3861(96)00333-3
  5. Journal of Colloid and Interface Science v.211 Surface modification of conventional polymers by depositing plasma polymers of trimethysilane and of trimethysilane+O₂: I. Static wetting properties Weikart,C.M.;Miyama,M.;Yasuda,H.K. https://doi.org/10.1006/jcis.1998.5963
  6. Polymer v.42 A new approach to characterize crystallinity by observing the mobility of plasma treated polymer surfaces Hyun,J.H. https://doi.org/10.1016/S0032-3861(01)00116-1
  7. Journal of Colloid and Interface Science v.202 Dynamics of polymeric solid surfaces treated with oxygen plasma: Effect of aging media after plasma treatment Murakami,T.;Kuroda,S.I.;Osawa,Z. https://doi.org/10.1006/jcis.1997.5386
  8. Polymer Composites v.11 Acoustic emission on single filament Kevlar/polymercarbonate composite under tensile deformation Ma,B.T.;Schadler,L.S.;Laird,C. https://doi.org/10.1002/pc.750110403
  9. Composites Science and Technology v.60 properties of interfacial adhesion for vibration controllerbility of composite materials as smart structures Park,J.M.;Kim,D.S.;Han,S.B. https://doi.org/10.1016/S0266-3538(00)00081-6
  10. Composite Part B: Engineering v.31 Impact damage charaterization of carbon fibre/epoxy composites with multi-layer reinforcement Sohn,M.S.;Hu,X.Z.;Kim,J.K.;Walker,L. https://doi.org/10.1016/S1359-8368(00)00028-7