Treatment of AlSi12 feedstock with water to manufacture multi-material parts by laser powder bed fusion process: A potential route for the fabrication of inorganic 3D metamaterials

Abstract

A new L-PBF process is proposed to manufacture, from a single powder chemically activated by pure hot water, parts comprising in selected areas of space, a ceramic or a metal alloy. The chemical activation of the starting alloy powder, the melting and densification of the metallic zones as well as the oxidation of metal alloy powder and sintering of the ceramic zones, have been studied and optimized. The results obtained allowed the realization of multi-material functional structures. Thus, small coaxial conductors have been fabricated. Beyond these relatively simple parts, 2D and 3D periodic structures made of ceramics and metal have been successfully realized. The achievement of these periodic structures gives hope for the further development of 3D inorganic metamaterials for microwave applications.

Keywords

• Metamaterials
• 3D multi-materials
• Aluminum-alumina assemblies
• Laser powder bed fusion
• Aluminum-water reaction
• Hydrogen generation