Microstructure evolution and mechanical behavior of SS316L alloy fabricated by a non-toxic and low residue binder jetting process

The metal binder jetting technology has demonstrated tremendous potential for low-cost batch manufacturing. However, the hazardous nature of the most frequently used phenolic-based binders and their high residual content restrict the application of binder jetting. In this study, an environmentally friendly PVA-based binder with high water content (up to 80 %) was designed and adapted for most commercial nozzles. The developed binder with high wettability enabled good bonding between the powder layers. A fully dense SS316L part with low carbon and oxygen residuals was obtained by a continuous debinding-sintering treatment. Fine equiaxed grains were found in the sintered sample, leading to an isotropic tensile property with an ultimate tensile strength (UTS) of 535 MPa and an extremely high elongation of 53 %.