Bulk Cu-NbC nanocomposites with high strength and high electrical conductivity

We report on a study aimed at simultaneously achieving high strength, high electrical conductivity and high thermal stability in bulk nanocrystalline (NC) Cu-NbC nanocomposites. We describe an approach that involves adding NbC nanoparticles (∼7 nm) into a nanocrystalline Cu matrix (∼96 nm) via in-situ formation during sintering of high energy mechanically milled powder into a compact. Our results show that the presence of thermally stable NbC nanoparticles in the bulk NC Cu-NbC nanocomposite contributes to a high tensile strength (868 MPa) in combination with a thermally stable nanocrystalline Cu matrix, and a high electrical conductivity of ∼56% IACS (International Annealed Copper Standard).