Enhancing Sustainability in Metal Additive Manufacturing Through Recycling Elemental Fe, Co, and Ni Powders and Subsequent Plasma Atomization

Laser powder bed fusion (L-PBF) is a metal additive manufacturing (AM) technique that utilizes high-power laser to selectively fuse metal powders, in a layer-by-layer manner, to create a 3D object. After LPBF process, there are often a substantial quantity of powders that is left unused. If the powders are not recycled, it becomes not cost-effective; however, directly reusing the used powders compromises the printed part quality. Therefore, we explored the feasibility of producing high-quality pre-alloyed FeCoNi powders through mechanical pre-alloying and plasma atomization of recycled elemental Fe, Co, and Ni powders. Extensive characterizations such as porosity, hardness, tensile, micrography, and chemical distribution were carried out to investigate the produced powders and the AM parts fabricated using them. It is revealed that the processed recycled powders showed markedly less defects than their as is condition. Through such approach, the sustainability for metal additive manufacturing and cold spray techniques can be significantly improved.