The layered metal-based material can achieve high performance and functionalization of the material by taking advantage of the composite effect of each component layer, the size effect of the enhanced phase and the interface effect. Among them, Cu/Ni layered metal composite materials have been widely used in fuel cell systems, heat exchange systems, and micro battery anode material container systems. However, during the hot-rolling composite molding process of traditional Cu/Ni layered composites, the difference in the diffusion rate of Cu and Ni atoms at the interface under high temperature conditions will cause Kirkendall holes to occur. This has always limited the development and application of layered metal composites that replace the mutual soluble system.
Since the discovery of the Kirkendall effect in 1947, the Kirkendall effect has been in a state of continuity. In 2011, Professor Yin Yadong used it as a nano-hollow material to make a new year. However, in the field of metallurgy, it greatly affects the interface of layered metal composite materials. Combining performance, so engineers worked to eliminate it.
Recently, Professor Yin Fuxing's team from the Institute of Energy Equipment and Materials Technology, School of Materials Science and Engineering, Hebei University of Technology published an article on "Materials Science & Engineering A" about graphene film regulating the interface and mechanical properties of Cu/Ni multilayer composites The article is entitled "Thickness effect of graphene film on optimizing the interface and mechanical properties of Cu/Ni multilayer composites". Creative use of graphene film to eliminate the Kirkendall effect, thereby significantly improving the interface bonding strength of the hot-rolled Cu/Ni layered composite material. At the same time, the strength and toughness of the composite material have also been significantly improved.
Paper link:
https://doi.org/10.1016/j.msea.2020.140111
Since the main reason for the strengthening of composite materials is the effective bearing of the reinforcement and the plastic deformation process that interrupts the matrix, the content, morphology and distribution of the reinforcement have an important influence on the properties of the composite. In addition, the mechanical properties of graphene are highly anisotropic, and the uniformly distributed structure cannot give full play to the advantages of the composite configuration of the material. Therefore, in this paper, the electrodeposition method + solution treatment method is used to introduce graphene to the layer interface, and the thickness of the graphene film is adjusted by adjusting the electrodeposition parameters, and then the importance of the composite interface design is discussed. Studies have found that a graphene film of appropriate thickness can effectively inhibit the asymmetric diffusion behavior of copper and nickel elements, reduce the formation of Kirkendall holes, strengthen the bonding strength of the copper/nickel interface, and effectively inhibit the premature localization of the nickel layer Neck and fracture damage, so that the material has a good uniform plastic deformation ability.