Bone-inspired enhanced fracture toughness of de novo fiber reinforced composites
Bone-inspired enhanced fracture toughness of de novo fiber reinforced composites
复制标题
DOI：
10.1038/s41598-019-39030-7
复制
发表时间：
2019-02-28
影响因子：
4.6
通讯作者：
Vergani, Laura
中科院分区：
文献类型：
--
作者：
Libonati, Flavia;Vellwock, Andre E.;Vergani, Laura
韧性的放大和刚度与强度的平衡是生物结构复合材料的基本特征，也是工程设计长期追求的目标。大自然通过多尺度关键特征的组合来实现这些属性。然而，将所有这些特征模拟到合成材料中是相当具有挑战性的。在这里，我们对手工层压进行微调，以实现新设计的骨启发结构到纤维增强复合材料中。将数值模拟、特别制造技术和测试相结合的综合方法，产生了一种新型复合材料，具有增强的断裂韧性和刚度与强度的平衡，提供了一种最佳的轻质材料解决方案，其性能优于金属和合金等传统材料。结果还表明，与传统的层压复合材料相比，新设计显著提高了断裂韧性，同时也提供了刚度和强度的最佳权衡。新材料断裂韧性增强的主要机制是裂纹不断偏离直线路径，促进大能量耗散，防止灾难性破坏。从这项研究中得出的新见解可以指导从头设计的纤维增强复合材料，以获得更好的机械性能，达到其天然对应物的协同作用水平。
Amplification in toughness and balance with stiffness and strength are fundamental characteristics of biological structural composites, and a long sought-after objective for engineering design. Nature achieves these properties through a combination of multiscale key features. Yet, emulating all these features into synthetic de novo materials is rather challenging. Here, we fine-tune manual lamination, to implement a newly designed bone-inspired structure into fiber-reinforced composites. An integrated approach, combining numerical simulations, ad hoc manufacturing techniques, and testing, yields a novel composite with enhanced fracture toughness and balance with stiffness and strength, offering an optimal lightweight material solution with better performance than conventional materials such as metals and alloys. The results also show how the new design significantly boosts the fracture toughness compared to a classic laminated composite, made of the same building blocks, also offering an optimal tradeoff with stiffness and strength. The predominant mechanism, responsible for the enhancement of fracture toughness in the new material, is the continuous deviation of the crack from a straight path, promoting large energy dissipation and preventing a catastrophic failure. The new insights resulting from this study can guide the design of de novo fiber-reinforced composites toward better mechanical performance to reach the level of synergy of their natural counterparts.