STABILITY AND DEFORMATION BEHAVIOR OF CELLULAR GRAPHENE COMPOSITE: MOLECULAR DYNAMICS

10.25712/ASTU.1811-1416.2024.02.006

Abstract

Composite materials, consisting of different components сombined together by physical and chemical bonds, are attracting increasing attention due to the growing demands on new functional materials. The search for new carbon materials that could become components of composite materials is currently of great interest. In this work, the stability and deformation behavior of a new composite material based on a nickel-filled cellular carbon structure have been studied using the molecular dynamics method. Cellular carbon structure is a honeycomb aerogel combined of graphene nanoribbons. As a result, an atomistic model of the composite has been constructed and its mechanical properties have been studied at 0 K and 300 K. In particular, compressive stability and tensile strength analysis have been studied. It is shown how the redistribution of the metal occurs inside the cells of the graphene matrix: the fcc lattice of nickel is transformed under the attraction of the graphene walls and the nickel atoms are stacked in layers, repeating the "pattern" of the graphene matrix. During the process of biaxial compression, a further change in the arrangement of nickel atoms inside the honeycomb cells occurs, leading to the formation of nickel layers parallel to the cell walls. Uniaxial tensile tests have been performed on three types of materials: pure nickel, a nickel-filled cellular structure, and a composite after biaxial compression. It has been shown that the strength of the composite increases significantly compared to pure nickel, and the strength is provided by the carbon network. The effect of temperature on the strength is weak, as is the influence of structure anisotropy. The results obtained demonstrate a new type of composite material with high strength.