Tailored Nickel Base Multilayer Systems with Adjusted Grain Size and Chemical Composition

Abstract

Metal multilayers exhibit improved material properties in a wide range of applications. Used as coatings, they can make a component more resistant to wear or corrosion in particular environments. Multilayer coatings can also be used to add additional properties to a component and make it multifunctional. The fabrication and characterization of multilayers are therefore an important issue. Herein, both the fabrication and characterization of Ni/Cu and nanocrystalline/coarse-grained Ni (nc/cg-Ni) multilayers are presented. The production by means of electrodeposition also allows a variation of layer thicknesses from a few nanometers up to a few hundred micrometers and is easily scalable to industrial application. This article describes the single-bath deposition and analyzes the microstructure and composition of the homogeneously deposited Ni/Cu and nc/cg-Ni multilayers. A modulation of hardness in nc/cg-Ni varying from 4.9 to 6.1 GPa is achieved while the elastic modulus is nearly constant. In Ni/Cu multilayers, hardness varies from 6.4 to 6.1 GPa in the Ni- and Cu-rich layers, respectively. Additionally, the reduced Young's modulus ranges from 187.2 (Ni-rich) to 169.8 GPa (Cu-rich). The layer interfaces in both sample types are tested using microbending cantilevers and are found be pore-free, mechanically stable and show crack-free plastic deformation.