液体模塑成型工艺用纤维织物厚度方向饱和渗透率的预测模型液体模塑成型工艺用纤维织物厚度方向饱和渗透率的预测模型
Prediction model of through-thickness saturated permeability of fabric for liquid composite molding

树脂在复合材料预成型体厚度方向的渗透能力对复合材料液体模塑成型工艺（LCM）的成功实施至关重要。本文采用连续加载的方式，研究了玻璃纤维增强树脂基复合材料液体成型过程中多轴向无屈曲织物（NCF）和斜纹织物（WF）的压缩响应行为，并建立描述该行为的数学模型。采用自制测试装置对预成型体在重力等不同注射压力驱动下的厚度方向渗透率进行测试，考察了预成型体纤维体积分数、测试流体注射压力等对预成型体厚度方向渗透率Kz的影响。基于预成型体压缩响应数学模型和厚度方向渗透率与注射压力的关系，对Kozeny-Carman公式进行修正，提出了变注射压力条件下的厚度方向渗透率预测模型。结果表明：预成型体厚度方向渗透率随着纤维体积分数的增大而减小，与Kozeny-Carman方程结果相符合。当纤维体积分数为0.42≤Vf≤0.58时，注射压力对厚度方向渗透率影响较大，实验结果验证了本文提出的预测模型；当纤维体积分数Vf≥0.58时，注射压力对厚度方向渗透率影响较小，厚度方向渗透率趋于恒定。 The penetration of resin along thickness is one of the most crucial factors in liquid composite molding (LCM). The method of continuous loading was used to study the compressive behaviors of non-crimp fabric(NCF) and woven fabrics(WF) during the liquid molding of glass fiber reinforced resin matrix composite respectively and a mathematical model was established to describe this behavior. The through-thickness permeability Kz of the preform under gravity and different injection pressures was tested by a self-made through-thickness permeability testing device. The influence of the preform fiber volume fraction and injection pressure on Kz of the preform was studied. Based on the preform compressive behavior model and the dependence of Kz on injection pressure, the Kozeny-Carman formula was modified and a through-thickness permeability prediction model was presented. The results show that the through-thickness permeability decreases with the increase of the fiber volume fraction of the perform Vf, which agrees with the Kozeny-Carman equation. As the fiber volume fraction varies in the region from 0.42 to 0.58, injection pressure has significant influence on the permeability, and the accuracy of the prediction model presented here is validated experimentally. However, when the fiber volume fraction is higher than 0.58, the injection pressure has little effect on Kz and Kz tends to be constant as Vf increases. 中央高校基本科研业务费专项资金（2018-zy-001