颗粒尺寸对碳纤维增强塑料中层状硅酸盐增韧机制的影响

Influence of Particle Size on Toughening Mechanisms of Layered Silicates in CFRP.

作者信息

Hutschreuther Julia, Kunz Raphael, Breu Josef, Altstädt Volker

机构信息

Bavarian Polymer Institute and Department of Polymer Engineering, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany.

Bavarian Polymer Institute and Department of Inorganic Chemistry I, University of Bayreuth, Universitätsstraße 30, 95447 Bayreuth, Germany.

出版信息

Materials (Basel). 2020 May 22;13(10):2396. doi: 10.3390/ma13102396.

DOI:10.3390/ma13102396

PMID:32455977

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7288157/

Abstract

Carbon-fiber-reinforced epoxies are frequently used for lightweight applications that require high mechanical properties. Still, there is potential regarding the improvement of the interlaminar-fracture toughness. As matrix toughening with nanoparticles is one possibility, in this study two different layered silicates are used to reinforce carbon fiber composites. The first type is a synthetical K-Hectorite (K-Hect) with outstanding lateral extension (6 µm) that has shown high toughening ability in resins in previous work. The other is a commercial montmorillonite (MMT) with a smaller size (400 nm). The aim of this study is to show the influence of the particles on mode I and mode II fracture toughness, especially the influence of particle size. Therefore, double-cantilever-beam tests and end-notched-flexure tests were carried out. Additionally, the fracture mechanisms were investigated via scanning electron microscopy (SEM). It is concluded, that the larger Hectorite particles are beneficial for mode I fracture behavior because of enhanced toughening mechanisms. One the other hand, the mode II energy dissipation rate is increased by the smaller montmorillonite particles due to sufficient interaction with the formation of hackling structures.

摘要

碳纤维增强环氧树脂常用于需要高机械性能的轻量化应用中。然而，层间断裂韧性仍有提升空间。由于用纳米颗粒增韧基体是一种可行方法，本研究使用两种不同的层状硅酸盐来增强碳纤维复合材料。第一种是合成的K-锂皂石（K-Hect），其具有出色的横向延伸（6 µm），在先前的工作中已显示出在树脂中具有高增韧能力。另一种是商业蒙脱石（MMT），尺寸较小（400 nm）。本研究的目的是展示颗粒对I型和II型断裂韧性的影响，特别是颗粒尺寸的影响。因此，进行了双悬臂梁试验和端部切口弯曲试验。此外，通过扫描电子显微镜（SEM）研究了断裂机制。得出的结论是，较大的锂皂石颗粒由于增韧机制增强，对I型断裂行为有益。另一方面，较小的蒙脱石颗粒由于与劈裂结构的形成有充分相互作用，提高了II型能量耗散率。