Micromechanical characterisation of Ni/Al hybrid foams by nano- and microindentation coupled with EBSD

Abstract

Metal foams are a very interesting class of cellular materials that is often used for lightweight construction or as energy absorbers. Ni/Al hybrid metal foams are a new and innovative composite foam material, consisting of nano-nickel coated aluminium foams. Since the mechanical properties of foams are strongly related to their microstructure, in Ni/Al hybrid foams, the coating is an additional degree of freedom affecting the mechanical properties of the foams. For meaningful simulations of the material behaviour, a detailed knowledge of the material properties of both the coating and the aluminnium struts is necessary.In this study, the micromechanical material parameters of Ni/Al hybrid foams are evaluated by means of nanoindentation and microindentation of the Ni coating and the Al struts. The indentation methods were coupled with electron backscatter diffraction (EBSD) in order to combine the determined parameter with the local grain structure.