Validation Of Alternative Binders for Pellet Extrusion 3D Printing Of 316L Steels

Composite Extrusion Modelling (CEM) is an attractive additive manufacturing process based on material extrusion techniques for rapid low-cost production of complex products using feedstock in the shape of granules instead of filaments. In this work, a novel water-soluble binder based on the combination of polyethylene glycol (PEG) and cellulose acetate butyrate (CAB) is used to develop 316L stainless steel feedstocks, which are compared with two feedstocks used in powder injection molding (MIM) and Fused Filament Fabrication (FFF). The study and comparison of the feedstocks are based on: 1) characterization of the viscosity of the three feedstocks to study the influence of the different binder compositions during their deposition; 2) optimization of the printing parameters of the different feedstocks to ensure their structural integrity and densification of the parts in subsequent processes. In addition, the debinding and sintering process of the samples was carried out, and the microstructural properties of the final parts were analysed.