预浸料的铺放适宜性评价(二)--铺覆性篇

ASSESSMENT FOR PLACEMENT SUITABILITY OF PREPREG-PART OF DRAPE

在自动铺带成型过程中,粘性和铺覆性是用于描述预浸料是否适合铺贴的两个重要因素,将粘性和铺覆性分别独立地研究能更好地理解预浸料的铺放适宜性。本文主要针对预浸料的铺覆性进行了探索,论述了铺覆性的含义并总结了现有的预浸料铺覆性的定量表征方法,提出了以"最大弯曲力"定量表征预浸料的铺覆性,并通过三点弯曲试验研究了预浸料的粘弹性特征及自动铺带成型过程中的主要工艺参数(铺放速率、湿度、热风温度、老化时间等)对预浸料铺覆性的影响。实验结果表明,预浸料的铺覆性会随热风温度和湿度的升高而提高,随着老化时间和铺放速率的增加而减小。最后总结了铺覆性实验的工程意义,为自动铺带工艺参数的控制提供了参考。

In the process of automated tape laying （ATL）, tack and drape are two characteristics that describe the suitability of prepreg for lay-up. Tack and drape researched individually can help us understand placement suit- ability of prepreg better. This paper aims at drape of prepreg. Firstly, the meaning of prepreg＇ s drape was dis- cussed and the existing measurement methods and quantitative characterization of prepreg＇ s drape were summa- rized; Secondly, using ＂Max. bending force＂ quantitatively characterizing the drape of prepreg was proposed and viscoelasticity of prepreg and influence of the main processing parameters of ATL, such as lay-up velocity, humidi- ty, hot-air temperature, aging time etc. , on prepreg＇ s drape were researched by three point bending test. The ex- perimental results indicate that prepreg＇ s drape increases with the higher temperature and humidity, but decreases with the longer aging time and lower velocity of lay-up ; Finally, the engineering significance of drape test was sum- marized, which provides a reference for the control of the processing parameters on ATL.