Department of Engineering Mechanics, South China University of Technology, Guangzhou, Guangdong 510640, P. R. China.
Phys Chem Chem Phys. 2019 Jan 30;21(5):2659-2664. doi: 10.1039/c8cp07477a.
Crack propagation in graphene monolayer under tear loading is investigated via an energy-based analytical model and molecular dynamics (MD) simulations. The classical mechanics-based model describes steady-state crack propagation velocity as a function of applied stress, lateral dimension and loading geometry, as well as the critical stress and critical size for initiating steady crack propagation. MD simulations reveal that cracks propagate along the zigzag direction but yield different "fracture surface" roughnesses for different loading geometries. MD simulations and the predictions of the analytical model are in excellent agreement. Our findings lead to an improved fundamental understanding of the mode-III crack of monolayer graphene necessary for the design and fabrication of graphene-based devices.
采用基于能量的解析模型和分子动力学(MD)模拟研究了 tear 加载下单层石墨烯中的裂纹扩展。基于经典力学的模型将稳态裂纹扩展速度描述为施加应力、横向尺寸和加载几何形状的函数,以及引发稳态裂纹扩展的临界应力和临界尺寸。MD 模拟表明,裂纹沿锯齿形方向扩展,但对于不同的加载几何形状,会产生不同的“断裂面”粗糙度。MD 模拟和解析模型的预测结果非常吻合。我们的研究结果提高了对单层石墨烯的 III 型裂纹的基本认识,这对于基于石墨烯的器件的设计和制造是必要的。