Manufacturing and characterization of components produced via fused deposition modeling (FDM) utilizing metal injection molding (MIM) feedstock with a focus on steel alloy 316L
In this project, a consumer-grade, fused deposition modeling (FDM) 3D printer designed by PRUSA Research s.r.o. of Prague, Czech Republic for use with filament materials was purchased. A screw extruder designed by Direct 3D of Milan, Italy to be used with pellet materials was also purchased and subsquently installed on the 3D printer. Metal Injection Molding (MIM) pellets containing a water-soluble binder system and 316L stainless steel powder were purchased from PolyMIM of Bad Sobernheim, Germany. Components built with the pellets on the printer were successfully printed, debinded, sintered, and characterized. The parts were printed at nozzle temperatures between 180°C and 200°C, at a layer height of 0.20mm and a nozzle diameter of 0.80mm. Density values ranged from 84% to 95% of theoretical density and can be improved with optimized debinding and sintering treatments. Metallography showed lower density near the surfaces of the built parts, in addition to porosity directly related to the printing process. Mechanical properties from tensile tests recorded a yield strength of 155 MPa, an ultimate tensile strnegth of 359 MPa, and an elongation of 24%. Future research will focus on different nozzles, layer thicknesses, and materials
