A molecular dynamics investigation of mechanical properties of graphene reinforced iron composite and the effect of vacancy defect distance from the matrix-fiber interface

Abstract

Graphene is a material of excellent mechanical properties, which make it an ideal fiber for reinforcing metal. Since iron is the most used metal in the world, reinforcing iron with graphene can reduce the overall requirement of material in any application where strength is demanded. However, the effect of graphene reinforcement on the mechanical properties of iron needs to be known before the industrial application of the composite. In this paper, we have investigated the mechanical properties of graphenereinforced iron composite by Molecular Dynamics (MD) method for various conditions. The properties were investigated by applying uniaxial tension on a modeled representative volume element (RVE). The findings in our study show that for only 9% fiber volume, the failure strength of iron increased 48.87% and Young's modulus 41.315%. The effect of temperature on the mechanical property of the composite was also studied because the knowledge is required for manufacturing products with the composite operating at a wide temperature range. MD analysis also revealed that the initiation of fracture is from the matrix-fiber interface. We also investigated how the distance of vacancy defects from the matrix-fiber interface affects the mechanical properties of the composite, which can be used to select a suitable manufacturing process. The results obtained from this study show that vacancy defects lower the strength at a greater extent as it gets closer to the interface.