Unveiling the synergistic deformation mechanism in three-dimensional continuous network graphene-reinforced copper matrix composites

Three-dimensional continuous graphene-reinforced copper matrix composites (3D-Gr/Cu) have excellent mechanical properties due to their special configuration and strengthening mechanisms. To figure out the deformation mechanism of 3D-Gr/Cu, atomic models of 3D-Gr/Cu with different configuration of graphene network (GN) and concentration of defects are constructed and studied by molecular dynamic simulations in this work. Atomic structure evolution during stretching process is investigated, and the mechanical properties of 3D-Gr/Cu, GN and Cu models are studied. Thereby, synergistic deformation between GN and Cu in 3D-Gr/Cu is revealed, and the deformation coordination between GN and Cu is regulated by GN structure and Gr/Cu interface. Furthermore, intrinsic defects in graphene with a suitable concentration help to construct the three-dimensional GN, improve the Gr/Cu interface bonding, and thus enhance the deformation coordination between GN and Cu. These results provide a profound explanation of the deformation mechanism and a new basis for defect engineering in 3D-Gr/Cu.