The Mechanical Performance of Aluminum Foam Fabricated by Melt Processing with Different Foaming Agents: A Comparative Analysis

The study presents the comparative analysis of the compressive response for the experimental aluminium foams of different parent alloys fabricated by melt processing with/without Ca additive and an expensive conventional TiH2 foaming agent or a cheap alternative CaCO3. It was recognized that the response of the foams is significantly dependent on the type of foaming agent and Ca additive due to the formation of low ductile and brittle products created in the foaming process. The presence of deformation bands and brittle eutectics in material, Al3Ti particles/layers, partially decomposed TiH2, Ca containing compounds, etc. cause a reduction of the foam's compressive strength and deviation of its mechanical profile from the theoretical predictions. In addition, the usage of an inexpensive CaCO3 foaming agent offers numerous indisputable advantages compared to TiH2, resulting, particularly, in enhancing the energy absorption ability of foams.