经编四轴向玻璃纤维织物的渗透行为和渗透率

Permeation behavior and permeability of warp-knitted quadri-axial glass fiber fabric

为研究经编四轴向玻璃纤维织物的渗透行为同织物结构的关系,采用径向法和单向法对不同铺层数和铺层角度的预制件进行面内渗透率以及单向渗透率的测试,并结合复合材料横截面切片对织物凹凸表面效应以及对流动的阻碍作用进行分析。采用以体积分数为自变量的经验公式对多层铺层织物的单向渗透率进行预测。实验结果表明:对于低铺层数的预制件,渗透率和纤维体积分数无直接关系,与织物表面在压缩作用下形成的平行于流动方向的流道数量密切相关;对于铺层角度不同的预制件,平行流道数目最多的预制件具有最大的渗透率;经验公式较Kozeny-Carman公式更能准确地预测经编四轴向织物的单向渗透率。

In order to study the relationship between the permeation behavior and the structure of warpknitted quadri-axial glass fiber fabric,the planar permeability and the unidirectional permeability of the preforms with different ply numbers and ply angles were measured by radical permeability test method and unidirectional permeability test method. The cross-section of the composite was analyzed to identify the impediment effect on flowing by fabric＇s concave and convex surface. The unidirectional permeability of multi-layer preforms was predicted by empirical formula with the variation of fiber volume fraction. The experimental results show that no direct relationship exists between the permeability and the fiber volume fraction in preform with lower ply numbers. However,the permeability is closely related to the number of flow channels which are formed by the fabric surface under compression and parallel to the flow direction.For preforms with different ply angles,the one with the largest number of parallel flow channels has the highest permeability. The empirical formula was more accurate compared with the Kozeny-Carman formula in predicting the unidirectional permeability of the warp-knitted quadri-axial glass fiber fabric.