Experimental investigation of randomly-oriented tow-based discontinuous composites and their equivalent laminates
Experimental investigation of randomly-oriented tow-based discontinuous composites and their equivalent laminates
复制标题
随机取向丝束基不连续复合材料及其等效层合材料的实验研究
DOI：
10.1016/j.compositesa.2017.06.031
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发表时间：
2017
影响因子：
8.7
通讯作者：
K. Schuffenhauer
中科院分区：
文献类型：
--
作者：
Yizhuo Li;S. Pimenta;Jordan Singgih;S. Nothdurfter;K. Schuffenhauer
等效层合板假设是模拟不连续复合材料随机结构的常用方法，但尚未得到实验验证。本研究旨在验证等效层合板假设，重点针对两种不连续纤维复合材料(TBDC)，与传统的不连续纤维复合材料相比，这种复合材料具有更高的纤维含量，从而提高了弹性模量和强度。这一验证是通过制造和测试(I)具有随机取向丝束的实际TbDC和(Ii)具有两种不同丝束厚度的等效层压板(ELs)来实现的。结果表明，ELS表现出与TBDC相同的破坏机制，并且随着丝束厚度的增加，ELS也被削弱。然而，ELS在局部纤维含量和局部两个方向上缺乏空间变异性，这使得ELS比TBDC更强。因此，等效层合板假设适用于预测不连续复合材料的弹性模数，但不能在不考虑其微观结构局部变异性的情况下预测其强度。
The equivalent laminate assumption is a commonly-used method to model the random architecture of discontinuous composites, but which has never been validated experimentally. This study aims to verify the equivalent laminate assumption, focusing on tow-based discontinuous composites (TBDCs), which have higher fibre-content and thus improved modulus and strength, compared to conventional discontinuous-fibre composites. This verification was achieved by manufacturing and testing (i) actual TBDCs with randomly oriented tows and (ii) their equivalent laminates (ELs), at two different tow thicknesses. The results show that ELs exhibit the same failure mechanisms as TBDCs, and are similarly weakened by an increase in tow thickness. However, ELs lack the spatial variability in local fibre-content and local tow orientations, which makes ELs stronger than TBDCs. Therefore, the equivalent laminate assumption is suitable for predicting the modulus of discontinuous composites, but cannot predict their strength without considering the local variability in their microstructure.