Fabrication and Characterization of Mg Rare Earth Alloy Closed-Cell Metal Foam Via Friction Stir Process for Enhanced Strength-to-Weight Ratio

This study investigated the microstructure and pore morphology, as well as the strength-to-weight ratio, of a fabricated Mg alloy foam. The precursor material was developed using WE43 Mg rare earth alloy as the substrate, with titanium hydride and aluminum powder serving as the blowing and stabilization agents, respectively. Micrographs revealed a homogeneous formation of small-sized pores in the central region of the stir zone, contrasting with heterogeneous and larger-sized pores along the advanced side. The pore sizes exhibited significant variation, ranging from 230 to 6.6 μm, with an average size of 57.35 μm, showcasing the intricate complexity of the foam’s structure. The fabricated metal foam decreased in density from 1.863 to 1.635 g/cc, while the strength-to-weight ratio increased from 174.9 to 178.59 compared to the substrate.