Interface effects on the properties of Cu–Nb nanolayered composites

Nanocrystalline metals possess high strength and outstanding resistance to irradiation damage. However, the high-density grain boundaries in nanocrystalline metals lead to low plasticity and poor thermal stability. In recent years, interface engineering has gradually become an important way to improve the comprehensive properties of nanocrystalline metals. In this paper, the interface structure, deformation mechanism, and physical properties of Cu–Nb nanolayered composites fabricated by physical vapor deposition and accumulative roll bonding are reviewed. Both Cu–Nb nanolayered composites possess semi-coherent interfaces. The nanolayered composites could achieve excellent resistance to irradiation damage since the interfaces are good sinks for the irradiation point defects. In addition, nanolayered metallic composites with abundant heterogeneous interfaces have better thermal stability compared to nanocrystalline metallic materials. Moreover, the interactions between dislocations and interfaces can be adjusted effectively through controlling the atomistic interface structure and alignment of slip systems across the interface, so as to achieve high strength and high plastic deformation ability simultaneously.