真空导入模塑工艺中织物预成型体的可压缩性

Compressibility of fabric preforms in vacuum infusion molding process

采用真空加载方法研究了循环加载、织物形态、纤维种类、织物层数、铺层方式和混杂方式等参数对真空导入模塑工艺(VIMP)中纤维织物预成型体压缩行为的影响。结果表明:预成型体纤维体积分数随着压缩循环加载次数的增加而逐渐增大,但增幅呈现逐渐减小的趋势;在相同的压缩载荷下,预成型体的纤维体积分数随着织物层数的增加而增大,但增幅很小,对于VIMP制备复合材料构件基本可以忽略;纤维预成型体在压缩载荷下的响应方式与织物形态、纤维种类、铺层方式和混杂方式等因素密切相关,单向铺层比正交铺层更容易压缩而获得较高的纤维体积分数,夹芯混杂比层间混杂方式更容易压缩。

The compressibility of fabric preforms in vacuum infusion molding process （VIMP） was studied by loading vacuum pressure. The effects of cyclic loading, fabric form, fiber type, number of layers, way of layup and hybrid mode on the compressibility were investigated. The results show that the fiber volume fraction increases with the times of cyclic loading, while the growth value decreases. The growth value of fiber volume fraction slightly increases with the number of layers under the same vacuum pressure that it almost can be neglected in vacuum infusion molding process（VIMP）. The way of layup, fabric form, fiber type and hybrid mode have remarkable effects on the compressibility of fabric preforms. The undirectional layup results in a higher fiber volume fraction than the orthogonal layup under the same compaction pressure, and the higher fiber volume faction can be achieved in the core hybrid composite compared with that in the interply hybrid composite.