Demonstration of pseudo-ductility in unidirectional discontinuous carbon fibre/epoxy prepreg composites
Demonstration of pseudo-ductility in unidirectional discontinuous carbon fibre/epoxy prepreg composites
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DOI：
10.1016/j.compscitech.2014.10.022
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发表时间：
2015-01
影响因子：
9.1
通讯作者：
G. Czél;S. Pimenta;M. Wisnom;P. Robinson
中科院分区：
文献类型：
--
作者：
G. Czél;S. Pimenta;M. Wisnom;P. Robinson
连续单向纤维增强复合材料固有的脆性是其优异机械性能的主要缺点。本文利用复合材料与重叠的不连续性在铺层水平创建一个显着的非线性响应，由于渐进层间损伤拉伸载荷下。两种不同的配置制造相同的碳/环氧树脂系统和准静态拉伸下进行测试，显示不同的厚度和长度的重叠层块导致显着不同的机械响应和故障模式。先前开发的广义剪切滞后模型被成功地用于优化重叠配置，并准确地预测在强度和韧性主导的情况下的响应。这项工作表明，在铺层水平上具有精心设计的不连续性的单向复合材料可以在失效前提供明显的非线性响应，同时保持相似的刚度和高达50%的连续对应物的强度。
The inherent brittleness of continuous unidirectional fibre reinforced composites is a major drawback to their otherwise outstanding mechanical performance. This paper exploits composites with overlapped discontinuities at the ply level to create a significantly non-linear response, due to progressive interlaminar damage under tensile loading. Two distinct configurations were manufactured with the same carbon/epoxy system and tested under quasi-static tension, showing that varying the thickness and length of the overlapping ply blocks resulted in significantly different mechanical responses and failure modes. A previously developed generalised shear-lag model was successfully used to optimise the overlap configuration, and accurately predicted the response in both strength- and toughness-dominated cases. This work demonstrates that unidirectional composites with well-designed discontinuities at the ply level can provide a significantly non-linear response with clear warning before failure, while retaining similar stiffness and up to 50% of the strength of their continuous counterparts.