Flow of quasi-spherical nanoparticles in liquid composite molding processes. Part I: Influence of particle size and fiber distance distribution
Flow of quasi-spherical nanoparticles in liquid composite molding processes. Part I: Influence of particle size and fiber distance distribution
复制标题
准球形纳米颗粒在液体复合材料成型过程中的流动。第一部分：颗粒大小和纤维间距分布的影响
DOI：
10.1016/j.compositesa.2019.105563
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发表时间：
2019-10-01
影响因子：
8.7
通讯作者：
Ziegmann, Gerhard
中科院分区：
文献类型：
--
作者：
Abliz, Dilmurat;Finke, Benedikt;Ziegmann, Gerhard
研究了两种准球形NPs（二氧化硅和薄水铝石）在液态复合成型（LCM）过程中的流动和过滤。采用“自上而下”和“自下而上”两种不同的方法制备纳米混悬液，并对注射前后的粒径进行了分析。同时，利用改进的图像处理技术和算法系统地表征了光纤距离分布。研究发现，“自上而下”法制备的纳米悬浮液可能呈现双峰分布，准球形NPs的过滤与颗粒尺寸的双峰分布特征和预制体的双尺度特征密切相关。此外，还确定了55%的阈值纤维体积分数（V-f），在该阈值下，所研究的预制体表现出从双尺度到单一微尺度多孔结构的临界相变。结果表明，在阈值V-f以上，即使少量的粗颗粒也会严重阻碍浸渍过程。
This paper studies the flow and filtration of two quasi-spherical NPs (silica and boehmite) during liquid composite molding (LCM) processes. The nanosuspensions are prepared differently by "top-down" and "bottom-up" approaches, and the particle size is analyzed before and after injection process. In parallel, the fiber distance distribution is systematically characterized using improved image processing techniques and algorithms. It is found that nanosuspensions that are prepared by "top-down" approach may show a bimodal particle distribution, and that the filtration of quasi-spherical NPs is closely related to the bimodal distribution characteristics of the particle size and the dual-scale characteristic of the preform. Furthermore, a threshold fiber volume fraction (V-f) of 55% is identified, at which the investigated preform shows a critical phase transition from dual-scale to single micro-scale porous structure. It is shown that above the threshold V-f even a small fraction of coarse particles can strongly hinder the impregnation process.