The texture and grain growth of Ni/Al-hybrid metal foams was investigated by electron backscatter diffraction (EBSD) and nanoindentation. Prior to the electrodeposition the aluminum foams have been pre-treated by a special pickling routine followed by an electroless deposition of zinc which prevents the dissolution of the aluminum foams in the acid electrolyte. Due to the typical columnar grain growth of electrodeposited nickel, the directly subsequent layer consist of more or less elongated grains that show a more or less strong texturing and a hardness that is already more than two times the hardness of the uncoated foam strut. But in contrast to bulk nickel and despite of the columnar grain growth due to the three-dimensional curved geometry of the struts there is a kind of structural induced isotropic grain orientation. Hence the superior mechanical properties of the Ni/Al-hybrid foams can be explained by the hard sleeve around the soft aluminum struts.
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