Optimization of Printing Parameters to Achieve High-Density 316L Stainless Steel Manufactured by Binder Jet 3D Printing

Binder jet 3D printing (BJ3DP) can manufacture large-scale complex and customizable metal parts with low cost and high efficiency, showing extensive application prospect in the field of manufacturing engineering. However, very few studies have focused on optimizing printing parameters to achieve near-full densification BJ3DP 316L stainless steel (SS) parts. Therefore, the printing-related parameters, i.e., layer thickness, roller traverse speed, and binder concentration, were optimized in the present study. The dimensional quality of green samples revealed that the layer thickness of 125 mu m, binder concentration of 60%, and roller traverse speed of 20 pps were the optimal parameters for printing green samples. Following sintering, the BJ3DP 316L SS samples printed by the optimal parameters exhibited a relative density of similar to 99.5%, along with X-/Y-/Z-direction linear shrinkages of similar to 18.7, similar to 17.4, and similar to 19.8%, respectively, in good agreement with those of the simulation results. Z-direction showed the highest value of linear shrinkage due to the presence of gravity during sintering. Meanwhile, the sintered 316L SS samples printed by the optimal parameters possess Vickers hardness of similar to 192 HV, which exceeds the values of the BJ3DPproduced 316L SS samples reported in the available literature, arising from their high relative density and the presence of similar to 6.9 vol.% delta-ferrite phase.

Automated summary

Binder jet 3D printing (BJ3DP) has the potential to manufacture large-scale complex and customizable metal parts with low cost and high efficiency. This study optimized the printing parameters and demonstrated the effects of the optimal parameters on the dimensional quality and hardness of green and sintered samples.