不同泊松比复合材料的层板断裂韧性和裂纹尖端应力场_张耀强.pdf

4 No.4 　　　　7 2006 12 FIBER CO POSITES Dec., 2006 1 2 张耀强 , 刘文庆 (1., 471003)(2., 200444) 　　 , ;-; ;:。 　;;;; Near-tip StressFieldof Crack and Fracture Toughnessin CompositeswithDifferent PoissonsRatio 1 2 ZHANG Yao-qiang , LIU Wen-qing (1.Henan University of Science an Technology, Luoyang 471003) (2.Instrumental Analysis Research Center, Shanghai University, Shanghai 200444) ABSTRACT　The fracture toughness an notch fracture strength of two kin s of composites laminateswith ifferent plane-Pois- son ratio is compare .It is foun that the fracture toughness an notch fracture strength of composites with low Poisson ratio is higher than that with the balance laminates.Their near-tip stress fiel of crack is stu ie with the complex variable-variational metho .The relation between principal stress orientation an fiber orientation is also stu ies in this paper.The result shows that the unique near-tip stress fiel of crack in these laminates with low Poisson s ratio is helpful to improve the notch fracture strength. KEYWORDS　Poisson s ratio;Crack;Fracture strength;Stress fiel ;Composites 1　　 A、B, 1。25mm, 1 2。 a , 1。 , 1 2 1。 [1, 2] , [3, 4] 。[5] 。 0.66 0.122 A、B , A、B , 。 2 　 1　 (:W-、L-、a-、r-) , 　　　　8 　　　　　 2006 1