真空辅助成型工艺中预成型体的厚度变化与过流控制

采用无接触式电涡流位移传感系统, 对真空辅助成型工艺中预成型体的厚度变化进行了实时监测。揭示了该成型工艺过程中预成型体的厚度变化规律, 并考察了树脂过流控制时间对制件厚度与纤维体积含量的影响。结果表明, 在整个工艺过程中预成型体的厚度变化可分为三个阶段: 在树脂浸入后, 预成型体厚度迅速增加; 在树脂过流控制阶段, 预成型体厚度变化较小且保持在较高水平; 在树脂管关闭后, 预成型体厚度迅速下降并逐渐趋于稳定。制件厚度与树脂过流控制时间的变化关系类似于正弦曲线, 在树脂过流控制时间约为10 min时, 纤维体积分数最低, 较无过流控制降低1.7%; 在树脂过流控制时间约为40 min时, 纤维体积分数最高, 较无过流控制提高1.6%。

Change in preform thickness throughout the vacuum assisted resin infusion process and the post-filling control

The non-contact electric eddy current displacement sensor system was applied to real-time monitor the preform thickness change throughout the vacuum assisted resin infusion(VARI) process.The compaction behavior of the preform during the VARI process was discussed.And the effect of the post-filling time on the preform thickness and the fiber volume fraction was studied.The result indicates that the compaction behavior of the preform can be divided into three stages: the preform thickness increases rapidly when the resin is infused;the perform thickness is almost not changed during the post-filling;the preform thickness decreases rapidly and drives to a stable value after that the resin-inlet is clamped.The final part thickness varies with the post-filling time,and the variation tendency is similar to a sinusoid.The fiber volume fraction is the lowest and decreases 1.7% compared with that without post-filling,when the post-filling time is about 10 min.And the fiber volume fraction is the greatest and increases 1.6% compared with that without post-filling,when the post filling time is about 40 min.