Abstract Aim of this research article was to study inter-granular fracture toughness of graphene containing edge crack. Molecular dynamics based simulations were performed in conjunction with AIREBO potential to study the crack tip behaviour in pristine and bi-crystalline graphene nanosheets. Higher value of linear dislocation density at the grain boundaries helps in improving the fracture toughness of bi-crystalline graphene, and trend was predicted to be independent of chirality vector in mode-I loading. Higher dislocation density imparts lower change in critical bond length with applied strain, which helps in improving resistance to crack growth. Additionally, switching between heptagon and pentagon rings positioning at the crack tip also helps in improving the fracture toughness of bi-crystalline graphene. Crack tip containing heptagon rings has positive effect on the fracture toughness of bi-crystalline graphene as compared to pentagon rings. Outcome of the analysis will provide new insights in fracture properties of bi-crystalline graphene that further helps in utilising graphene nanosheets in mechanically robust applications such as pressure barrier, nanocomposites and ion-separation.

中文翻译：

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双晶石墨烯纳米片的晶间断裂韧性

摘要 本研究的目的是研究含石墨烯边缘裂纹的晶间断裂韧性。基于分子动力学的模拟与 AIREBO 潜力结合进行，以研究原始和双晶石墨烯纳米片中的裂纹尖端行为。晶界处较高的线位错密度值有助于提高双晶石墨烯的断裂韧性，并且预测趋势与 I 型加载中的手性矢量无关。较高的位错密度使临界键长随外加应变的变化较小，这有助于提高抗裂纹扩展能力。此外，位于裂纹尖端的七边形环和五边形环之间的切换也有助于提高双晶石墨烯的断裂韧性。与五边形环相比，含有七边形环的裂纹尖端对双晶石墨烯的断裂韧性有积极影响。分析结果将为双晶石墨烯的断裂特性提供新的见解，进一步有助于将石墨烯纳米片用于机械稳健的应用，如压力屏障、纳米复合材料和离子分离。