• 文献标题:   Atomic simulations of the formation of twist grain boundary and mechanical properties of graphene/aluminum nanolaminated composites
  • 文献类型:   Article
  • 作  者:   ZHOU XH, LIU X, LEI J, YANG QS
  • 作者关键词:   graphene reinforced al composite, crystallization proces, twist grain boundary, dislocation motion, molecular dynamics simulation
  • 出版物名称:   COMPUTATIONAL MATERIALS SCIENCE
  • ISSN:   0927-0256 EI 1879-0801
  • 通讯作者地址:   Beijing Univ Technol
  • 被引频次:   2
  • DOI:   10.1016/j.commatsci.2019.109342
  • 出版年:   2020

▎ 摘  要

In this paper, generation of twist grain boundaries (TGBs) and their effects on the mechanical behaviors of graphene/aluminum (Gr/Al) nanolaminated composites were studied via molecular dynamics (MD) method. Crystallization of the Gr/Al composite was conducted to observe the microstructural evolution. The whole evolution process including nucleation and growth of crystals was presented. TGBs were formed between the adjacent crystals after crystallization. The fcc (1 1 1) plane of the Al matrix has three-fold symmetry, so that the TGB angles can range from 0 degrees to 60 degrees. Tensile tests on the Gr/Al composites with TGBs were carried out to study their deformation behavior. The results showed that the graphene-nanoplate (GNP) and TGBs greatly impact on the dislocation behavior of the Al matrix. The dependences of dislocation nucleation and evolution on the TGB angle were uncovered. The TGB also plays a significant role in blocking dislocation motion, and the effectiveness mainly depends on its strength. The variations of yield stress and strain of the Gr/Al composites with different TGB angles were also predicted. It was revealed that failure of the composite is caused by combined action of tensile deformation and shear deformation induced by defects at the GNP edge.