Influence of Cu, Zn and Si alloying elements on Al alloy foams produced using Mg blowing agent

The main focus of the present study is to compare the effect of different alloying elements on Al–Mg alloy foams. Al–Mg15–X10 (X = Cu, Zn and Si) alloy foams were produced via powder metallurgy route by using Mg as a blowing agent. Macro- and microstructural characterisations of the foams were performed using X-ray tomography, X-ray diffraction and scanning electron microscope. Corrosion studies such as weight loss measurement, hydrogen evolution method and potentiodynamic test were conducted. Mechanical properties were evaluated by subjecting the samples to quasi-static compression and microhardness tests. All the alloy foams showed a comparable structure. The Cu-containing foams exhibited the highest strength, while the Zn-containing foams showed the highest expansion. However, the other properties such as brittleness, elastic modulus and burning nature were found to be better for the Si-containing foams.