Mechanical characterization of open cell aluminium foams reinforced by nickel electro-deposition

The present study focused on the improvement of mechanical properties of open cell aluminium foams thanks to electro-deposition of nickel. In the first phase of the work, the parameters for the electro-deposition of nickel were optimized in order to increase the mechanical properties of these cellular materials. Different values of deposition currents and times were considered to vary the amount of nickel deposited. The performance improvement was evaluated by means of stress–strain curves. Strains were measured using a specifically developed optical extensometer with a resolution in strain of 14.1 micro-strains. A very low compression speed was set to provide a good temporal resolution given the type of camera used. Mechanical properties of aluminium foams coated by nickel or copper were compared according to the defined procedure to identify the effect of material and thickness of the coating. Stiffness was found not to be significantly affected by the electro-deposition of copper or nickel. On the contrary the maximum specific stress has been dramatically improved by the nickel coating. [Display omitted] •Deposition time between 20 and 60min allows a smooth and uniform coating.•Deposition current of 1.5A allows a smooth and uniform coating.•Copper has not been found to improve mechanical properties.•Nickel greatly enhances the absorbed energy for 60min and 1.5A.