Abstract Bioinspiration can lead to exceptional mechanical properties in a number of biological materials as a result of their internal structure. In particular, the hierarchical arrangement of nano-to macro-components can bring to complex energy dissipation mechanisms and unprecedented resistance to crack growth. In this work, we propose to exploit this approach, combining in a multiscale composite structure carbon nanotubes with conventional carbon fibre reinforcements in a polyvinyl butyral matrix. We show that grafting the nanotubes onto the carbon microfibres improves their interface properties with the matrix considerably, effectively doubling their apparent strength. At the same time, the addition of nanotubes to microfibre reinforcements helps to improve the composite toughness, reaching more than twice the value for the conventional, non-hierarchically reinforced composite. Numerical simulations and fracture mechanics considerations are also provided to interpret the results.

中文翻译：

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将碳纳米管接枝到碳纤维上，使其有效强度和复合材料的韧性加倍

摘要 由于其内部结构，生物灵感可导致许多生物材料具有卓越的机械性能。特别是，纳米到宏观组件的分层排列可以带来复杂的能量耗散机制和前所未有的裂纹扩展阻力。在这项工作中，我们建议利用这种方法，将多尺度复合结构碳纳米管与聚乙烯醇缩丁醛基质中的常规碳纤维增强材料相结合。我们表明，将纳米管接枝到碳微纤维上可以显着改善它们与基体的界面特性，有效地将它们的表观强度加倍。同时，在微纤维增强材料中添加纳米管有助于提高复合材料的韧性，达到传统材料的两倍以上，非分层增强复合材料。还提供了数值模拟和断裂力学方面的考虑来解释结果。