Producing metallic parts using 3D printing of low-viscosity powder-biner feedstock: A feasability study
Côté, R.; Demers, V.; Demarquette, Nicole R.; Charlon, S.; Soulestin, J. (2023). Producing metallic parts using 3D printing of low-viscosity powder-biner feedstock: A feasability study. AIP Conf. Proc. 2884, 170005 (2023).
The possibility to fabricate metallic parts by material extrusion additive manufacturing of highly-filled polymer (MEAM-HP) with low-viscosity feedstock has been demonstrated in this study. Quality parts were successfully printed using a laboratory plunger-based printer and two feedstocks consisting of stainless-steel powder blended with two different compositions of organic binders made of ethylene-vinyl acetate (EVA), paraffin wax, and stearic acid. Using the first feedstock, containing 5 vol. % EVA, dimensionally stable parts were printed only for a feedstock temperature of 70 °C, while with the second feedstock, containing 10 vol. % EVA, stable parts were printed within a larger feedstock temperature range of 70 to 140 °C. The minimum feedstock temperature was defined at 85 °C to guarantee sufficient adhesion between beads and limit binder shrinkage during the cooling. Using this optimal process parameter, complex-shape parts were successfully printed confirming that complex surfaces, bridging, and overhang structures can be produced using low-viscosity feedstock without help of supports.