An experimental investigation of screw-based material extrusion 3D printing of metallic parts

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

“…The temperature of the beginning and end of the barrel can be adjusted up to 300 °C. Full details of this 3D printer are stated in reference of 5 [5]. The optimal temperature at the beginning and end of the barrel is 140 and 180 °C respectively, the nozzle diameter is 0.5 mm, the width of extrusion is 0.6 mm, the height of layer is 0.3 mm, the chamber temperature is 60 °C, and the printing speed is 10 mm s −1 .…”

“…Without post-processing, the 3D printed samples are very brittle. So applying a little force to them lead to the failure of them [5]. The stress-strain diagram of the sintered samples is shown in figure 3.…”

“…Today, additive manufacturing (AM) [1] processes and the use of 3D printers have made significant progress [2][3][4][5][6][7]. Most metal products that are produced by AM processes are laser powder bed fusion processes.…”

“…The granules are heated higher than the grass transition temperature by heat and friction after passing through the transition zone, and the molten materials are under pressure before exiting (extruding) from the nozzle [1,20]. One of the processes for producing metal parts is the metal powder injection molding (MPIM) process [5,20,21]. In this process, a combination of metal powder and several polymers is produced in the form of granules, and these granules are used as raw (feedstock) materials.…”

“…After the injection and manufacturing of the part, the first process is to eliminate the binders before sintering, which is called the debinding process [22,23]. Sintering is a heat-treatment process to create a continuous bond between the particles and finally obtain a solid structure assisted by mass transfer [3,5]. Singh et al [18] studied on extrusion-based 3D printing of metal parts using feedstock of MPIM process.…”