ABSTRACT We conducted an in situ study on CFRP fracturing process using atomic-force-microscopy-based stress-sensitive indentation. Tensile stress distribution during fracture initiation and propagation was directly observed quantitatively. It led to a discovery that previously believed catastrophic fracture of individual carbon fiber develops in a controllable manner in the polymer matrix, exhibiting 10 times increase of fracture toughness. Plastic deformation in crack-bridging polymer matrix was accounted for the toughening mechanism. The model was applied to explain low temperature strength weakening of CFRP bulk material when matrix plasticity was intentionally ‘shut down’ by cryogenic cooling.

中文翻译：

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应力图揭示了聚合物基体中脆性碳纤维的外在增韧

摘要 我们使用基于原子力显微镜的应力敏感压痕对 CFRP 压裂过程进行了原位研究。直接定量观察断裂起始和扩展过程中的拉伸应力分布。它导致了一个发现，以前认为单个碳纤维的灾难性断裂在聚合物基体中以可控的方式发展，断裂韧性增加了 10 倍。裂纹桥接聚合物基体的塑性变形被解释为增韧机制。该模型用于解释当基体塑性通过低温冷却有意“关闭”时 CFRP 散装材料的低温强度减弱。