Effects of the graphene/metal interface on elastic properties of Cu and W matrices: Molecular dynamics simulation

Abstract

The present study aimed to investigate the effects of graphene/metal interface on the elastic properties of Cu and W matrices over a wide range of temperatures through molecular dynamics (MD) simulations. Results showed that the addition of graphene to Cu and W matrices can improve their Young's moduli, with higher enhancements observed at higher graphene fractions. The load transfer mechanism was employed to analyse the reinforcing effect of graphene in metal matrices, and the load transfer rates were subsequently calculated. The strengthening effect of graphene in Cu matrix was observed to increase significantly with rising temperatures, whereas that of G-W models decreased due to the decreasing load-carrying capacity of graphene at very high temperatures. Furthermore, the Poisson's ratio of Cu-based materials decreased with increasing strain, while that of W-based materials remained nearly constant. This behaviour can be attributed to the prominent surface effect of lateral stress and the crystal structure transformation observed in Cu-based materials. Notably, a negative Poisson's ratio was observed in G-Cu nanoplate when the vertical stress became compressive. Overall, this study provides insights into the elastic deformation behaviour of graphene/metal composites, which could help develop new graphene-reinforced Cu or W composites.