Dislocation Entangled Mechanisms in Cu-Graphene Nanocomposite Fabricated by High-Pressure Sintering

Graphene reinforced Cu-based nanocomposite (Cu-Gr), synthesized using high-pressure forming (∼8 GPa) route at 300 °C, achieved 96% of relative density and 84% IACS improvement in electrical conductivity, along with a significant increase in hardness and Young's modulus up to ∼94 GPa. The structure and defects evolution of NC-Cu and Cu-Gr nanocomposites were investigated using nanoindentation approach, and then backed up computationally. Molecular dynamics (MD) simulations results are well agreed with experimental data, which significantly reveled that grain growth and grain boundary sliding (GBS) are dominant deformation mechanism involves grain boundary movement through dislocation motion, stacking faults (SFs) and twin boundary (TBs) formation, along with matrix failure through grain growth and GBS with an increase in loading, and subsequently bending (bow shape) processes.