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Metallic foams are gaining ground as important new engineering materials.Aluminium foams were produced with different densities using different percentages of calcium carbonate as a foaming agent. The mechanical properties of the foamed material were tested using uniaxialcompression test. Plateau stress σpl, densification strain εd and energy absorption capacity U, were calculated. The obtained results show that the collapse strength and the absorbed energy of foams increase with increasing the density.

Zinc-based alloys have found many applications in recent decades. Such alloys are characterized by low melting points and high fluidity which make them suitable for foundry applications. The current study was carried out to select ZA alloys, typically ZA-8, ZA-12 and ZA-27. The effect of casting temperature, Al content, Si addition, and heat treatment on the properties of selected alloys was investigated. The result reveals that an increase in casting temperature enhances the measured hardness for all studied alloys. Also, the presence of Si in alloys in addition to the increase of Al content in alloys seems to improve the hardness and mechanical properties of alloys. Heat treatment of such a group of alloys had an adverse effect on the final properties of the alloy, as the heat treatment samples show a lowering in hardness compared to as cast samples. In addition, it was found that using of water as a cooling media instead of air enhances the final hardness of all alloys.