Production of Open-Cell Metal Foams by Recycling of Aluminum Alloy Chips

In this paper, an innovative sustainable method of producing metal foams was presented. The base material was aluminum alloy waste in the form of chips obtained by machining process. The leachable agent, used to create pores in the metal foams, was natrium chloride, which was later removed by leaching, resulting in metal foams with open cells. Open-cell metal foams were produced with three different input parameters: volume percentage of natrium chloride, compaction temperature, and force. The obtained samples were subjected to compression tests during which displacements and compression forces were measured to obtain the necessary data for further analysis. To determine the influence of the input factors on the selected response values such as relative density, stress and energy absorption at 50% deformation, an analysis of variance was performed. As expected, the volume percentage of natrium chloride was shown to be the most influential input factor because it has a direct impact on the obtained metal foam porosity and thus on the density. The optimal values of the input parameters with which the metal foams will have the “most desirable” performances are a 61.44% volume percentage of natrium chloride, a compaction temperature of 300 °C and a compaction force of 495 kN.