标题：Nano-graphene toughened Al2O3 ceramic materials: 3D simulation of the fracture behaviour
作者：Sun Z.; Zhao J.
作者机构：[Sun, Z] Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE, School of Mechanical Engineering, Shandong University, Jinan, 2500 更多
通讯作者地址：[Zhao, J] Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE, School of Mechanical Engineering, National Demonstration Center f 更多
关键词：Cohesive zone method; Fracture behaviour; Simulation model; Toughening mechanisms
摘要：A 3D simulation model of graphene toughened Al2O3 ceramic materials had been developed to study the fracture behaviour. Voronoi tessellation was used owing to its high similarity to the ceramic grain distribution. In addition, a new method to automatically generate nano-graphene along the Al2O3 grain boundaries was proposed. The Al2O3/graphene interface properties were characterised by the cohesive zone method, wherein cohesive elements along grain boundaries and in grains were generated using Python. Furthermore, the effects of phase interface bonding strength and graphene content on the fracture behaviour were analysed. The results clearly showed the occurrence of both intergranular and transgranular fractures. In addition, some toughening mechanisms induced by nano-graphene such as crack guiding, crack bridging, crack branching, microcracks, and pull-out of graphene have been discussed. The finite element simulation results were consistent with the experimental ones. Therefore, the results presented in this study would be beneficial for improving the design efficiency of Al2O3/graphene ceramic materials. © 2020 Elsevier Ltd and Techna Group S.r.l.