仿生石墨烯增强纳米复合材料力学性能的跨尺度数值模拟和实验研究

Cross-scale Numerical Simulation and Experimental Study of the Mechanical Properties of Bionic Graphene-Reinforced Nanocomposites

为了从微观层面解释仿珍珠层的增强机理,本文设计了一种石墨烯交错排布增强聚甲基丙烯酸甲酯的纳米复合材料,从分子动力学基础上建立有限元力学模型,模拟研究了大尺寸下石墨烯的几何形状和排布尺寸对仿生石墨烯增强聚合物复合材料拉伸和弯曲性能的影响,进一步对比宏观和微观尺度下模型的变形机制与性能变化的关系。最后,结合有限元仿真和实体实验方法研究了微结构对仿珍珠层结构材料力学性能的影响。模拟和试验结果表明:硬质层的形状、厚度、排列方式都会影响材料的强度。通过改变这些参数能够得到最优的力学性能。

In order to explain the strengthening mechanism of the pearl-like layer at the microscopic level,a graphene staggered arrangement reinforced polymethyl methacrylate nanocomposite was designed in this paper,and a finite element mechanical model was established from the molecular dynamics basis to simulate and study the effects of graphene geometry and arrangement size on the tensile and bending properties of the pearl-like reinforced polymer composite at large size,and further compare the macroscopic and microscopic scale.The relationship between the deformation mechanism and the property change of the model under macroscopic and microscopic scales is further compared.Finally,the effect of microstructure on the mechanical properties of the pearl-like layer structure material was investigated by combining finite element simulation and solid experimental methods.The simulation and experimental results show that the shape,thickness and arrangement of the hard layer affect the strength of the material.Optimal mechanical properties can be obtained by changing these parameters.