Powder condition and spreading parameter impact on green and sintered density in metal binder jetting

Abstract

Metal binder jetting is a high throughput additive manufacturing process of growing interest. The progress is driven by improvements in machine technology, enabling the processing of finer powders to produce homogeneous, dense final parts. However, the strong cohesive forces of fine metal powders impair flowability, packing behaviour and thus the properties relevant for powder spreading. This paper investigates the impact of powder condition and spreading parameters on green and sintered density using an Analysis of Variance. Parts from dried and from untreated powder are printed, varying in layer thickness, roller diameter, supply-to-spread ratio, translational and rotational roller speed. Powder drying increases the statistical impact of the spreading parameter and improves the green density, while the sintered density remains unchanged. Layer thickness and roller diameter have the most significant effect. Furthermore, the spreading parameter combinations that resulted in a high green density also provided a high sintered density.

Analysis of the Flatness Form Error in Binder Jetting Process as Affected by the Inclination Angle

“…demonstrated by Lores et al, using the same printing machine and a similar printing setup with 17-4 PH stainless-steel powder [35]. According to the ANOVA study of Barthel and Wieland, samples with a higher green density achieve a higher sintered density and higher dimensional change [36].…”

A review—metastable β titanium alloy for biomedical applications

“…The chosen additive manufacturing method, as well as the quality Ti and its alloy powder, has a substantial effect on the quality of implants made via additive manufacturing. The biomaterials are produced using additive manufacturing techniques such as directed energy deposition [70], laser-based powder bed fusion of metals (PBF-LB/M) [71], powder fed system of binder jetting [72], electron beam powder bed fusion of metals (PBF-EB/M) [73], plasma atomization [74], gas atomization [75], and plasma rotating electrode process [76].…”

Compensation of sintering deformation for components manufactured by metal binder jetting using numerical simulations

“…However, the manufacturing elements used to fabricate the specimens in the current study differ in printer, powder size distribution (PSD), printing layer thickness and sintering cycle from those in the research by Sadeghi Borujeni et al Nevertheless, some of material parameters including apparent, bulk and shear viscosity, as well as grain size are mainly affected by temperature, initial grain size, relative density and diffusion coefficients and not dependent on the reported differences (Olevsky, 1998; Riedel and Blug, 2002; Zhang et al , 2021). Therefore, those material parameters are borrowed from Sadeghi Borujeni et al However, densification behavior depends directly on PSD (Mostafaei et al , 2019; Chen et al , 2021), printing layer thickness (Barthel et al , 2021) and sintering cycle (Mostafaei et al , 2016; Huber et al , 2021). Thus, using a cylindrical specimen manufactured by new manufacturing elements, the phenomenological model used for the calculation of sinter stress given in equation (1) is tuned through a dilatometry experiment.…”

“…(Olevsky, 1998;Riedel and Blug, 2002;Zhang et al, 2021). Therefore, those material parameters are borrowed from Sadeghi Borujeni et al However, densification behavior depends directly on PSD (Mostafaei et al, 2019;Chen et al, 2021), printing layer thickness (Barthel et al, 2021) and sintering cycle (Mostafaei et al, 2016;Huber et al, 2021). Thus, using a cylindrical specimen manufactured by new manufacturing elements, the phenomenological model used for the calculation of sinter stress given in equation ( 1) is tuned through a dilatometry experiment.…”