A synergistic approach to the development of lightweight aluminium-based porous metallic foam using stir casting method

Introduction. A synergetic approach to the development of lightweight aluminium metal foam by stir casting process is presented and various mechanical properties and microstructure are tested. The purpose of this study is due to the constant industrial demand for lightweight materials and increased research interest in porous substrates, mainly due to its unique properties. Materials and method.. The method used for developing metallic aluminium foam was stir casting with calcium carbonate as a foaming agent to achieve a target interconnected porous microenvironment on a metal foam substrate. Results and Discussion. A set of physical properties, such as apparent density (1.8 g/cm3), relative density (0.67 g/cm3) and porosity (30 %) of the developed aluminium-based metal foams, is stated as the result. The developed metal foam has a strength-to-weight ratio 67 % higher than that of the base material. In addition, the results of field emission scanning electron microscopy of the developed metal foam confirm the presence of a porous network with a pore size from 0.075 mm to 1.43 mm. Energy dispersive spectroscopy confirmed the presence of the desired elements with minimal contamination in the developed aluminium foam substrates. Metal foam demonstrates a higher compressive strength (607 kN) compared to the base metal (497 kN). The mechanical characteristics of the developed metal foam substrate (hardness, compressive strength and impact energy) show the expected results compared to the base material. In general, the developed aluminium foam substrate established a promising route to the development of highly performance lightweight metal foam for shock absorber and acoustic applications.