Synthesis and Properties of Mg-Based Foams by Infiltration Casting Without Protective Cover Gas

Fabrication and characterization of Mg-based scaffolds by infiltration casting, without protective cover gas, are presented. Distinctive results were observed among the foams depending on the precise selection of casting variables. Foams with pore sizes ranging from 590 to 1040 µm, porosities ranging from 60.01 to 79.35%, and measured Young’s moduli ranging from 0.8 to 1.9 GPa, were obtained. These architected parameters for this cellular material were found to match the structural properties of cancellous bone while satisfying the mechanical requirements to support the bone healing process (0.3-3 GPa). Casting temperature and melting time were set at 680 °C and 10 min for infiltrating 590 µm salt particles. A salt flux combination containing MgCl₂, MgO, CaF₂, and KCl, is used to protect the molten metal, and its effect on ignition and oxidation of the Mg alloy is evaluated. The results of the crystalline phase and chemical analysis indicate a safe production process since there is no evidence of high contamination or new-formed phases.