Investigating the mechanical properties of sintered 440 C stainless steel produced by an extrusion-based 3D printer

Abstract

Extrusion-based 3D printing of parts is one of the simplest, cheapest, and most widely used additive manufacturing (AM) methods. The raw materials in this process are generally filaments with a constant diameter. By equipping extrusion-based 3D printers with the barrel and screw system and removing the filament manufacturing step, a wide range of materials can be 3D printed. In this research, the parts were 3D printed using a feedstock of metal powder injection molding process and with a direct granule extruder system equipped with a barrel and screw. Then, on the printed parts, debinding, sintering, and grinding processes were performed, and finally, their tensile and impact mechanical properties were evaluated. The average tensile strength and modulus are equal to 295 MPa and 85 GPa, respectively, the average of impact resistance is equal to 12.5 J and the hardness number is equal to 118 HB. In addition, by calculating the amount of porosity in the samples, the low value of the mechanical properties of the samples was justified.