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This paper makes an analysis of the interlaminar shear and tension stresses of the composite material laminate plate by the finite element with three dimensional elements,and a computation of the stress distributions and deformation of the non-symmetric laminate.Analysis is also made of the worping deformation; arising from hygrothermal strain by taking the elastic modulus of the material as a function of temperature and specific moisture concentration 本文用三维体元对复合材料层合板的层间剪切应力和拉(压)应力进行分析,同时计算了非对称层合板的应力分布和变形。文中分析了湿热应变引起的翘曲变形,并考虑了结构材料弹性系数是温度和水分比浓度的函数。 Styrene-co-maleic anhydride, vinyl acetate-co-maleic anhydride, methyl methacry-late-co-maleic anhydride copolymers were deposited on the surface of carbon fibers by an electrodeposition technique. The anion-free radical mechanism of this process and the physical adhesiton to, the surface were preliminarily confirmed. The adhesion at fiber-resin matrix interface in carbon fiber reinforced plastics was improved by the electrodeposited polymer interlayer and the shear failure occurred mainly in the matrix. Interlaminar... Styrene-co-maleic anhydride, vinyl acetate-co-maleic anhydride, methyl methacry-late-co-maleic anhydride copolymers were deposited on the surface of carbon fibers by an electrodeposition technique. The anion-free radical mechanism of this process and the physical adhesiton to, the surface were preliminarily confirmed. The adhesion at fiber-resin matrix interface in carbon fiber reinforced plastics was improved by the electrodeposited polymer interlayer and the shear failure occurred mainly in the matrix. Interlaminar shear strength of the unidirectional carbon fiber reinforced epoxy composite is increased from about 600 kg/cm2 to 1,000 kg/cm2 by electrodeposition of polymers and the strength loss of the composite which lias been immersed in boiling water for 100 hrs. is decreased. 用电沉积方法将苯乙烯-马来酸酐、乙酸乙烯酯-马来酸酐、甲基丙烯酸甲酯-马来酸酐共聚物沉积于碳纤维表面。通过实验初步证实了此过程的负离子-自由基机理,以及沉积层在纤维表面的物理粘附。由于电沉积的聚合物中间层改善了碳纤维增强塑料中纤维-基体树脂间的界面粘接作用,使原来的剪切破坏基本上发生于界面的情况转变成发生于基体本身为主。并将单向碳纤维增强环氧树脂复合材料的层间剪切强度,由原来的600kg/cm~2左右提高到1000kg/cm~2以上,经沸水浸泡100小时后的强度损失也减少了。 For test specimens built up symmetrically from 16 layers of fiber reinforced material the stress distributions are calculated under axial and thermal loads.Though the stresses are assumed constant in the axial direction volume elements are necessary to include interlaminar shear and peeling stresses.But the number of degrees of freedom and the bandwidth of the system matrix can be kept relatively low.The results show quite distinct stress peaks at layer interfaces,and it was found that even with 16 quadratic... For test specimens built up symmetrically from 16 layers of fiber reinforced material the stress distributions are calculated under axial and thermal loads.Though the stresses are assumed constant in the axial direction volume elements are necessary to include interlaminar shear and peeling stresses.But the number of degrees of freedom and the bandwidth of the system matrix can be kept relatively low.The results show quite distinct stress peaks at layer interfaces,and it was found that even with 16 quadratic elements over the layer thickness these values have not reached an acceptable accuracy.The convergence behavior gives rise to the conjecture,that infinite stresses may occure at those points.Making use of the substructure technique a few examples with different stacking sequences were analyzed.The results are compared to obtain a set-up with small edge stresses. 本文对用16层纤维增强材料对称铺设成的试样,在轴向载荷和热载下的应力分布作了计算。虽然沿轴向应力假定为常数,但在体积元素中必需包括层间剪应力和剥离应力。然而,系统矩阵的自由度数和带宽能保持比较低。计算结果表明,在铺层分界面上有十分明显的应力峰,並发现,即使沿铺层厚度使用16个二次元素,这些值仍没有达到令人满意的精度。由于这样的收敛性能,推测在这些点可能发生无限大的应力。本文应用子结构方法分析了少量具有不同铺设顺序的例子。比较这些分析结果,得到了一种产生小边缘应力的铺设顺序。
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