A thorough investigation into the effects of powder size distribution during the powder spreading step in a binder jetting process is conducted using ceramic foundry sand. It was observed that coarser particles result in higher flowability (62% decrease in repose angle) than finer ones due to the cohesion effect present in the latter. A bimodal size distribution yields the highest packing density (8% increase) and lowest porosity (∼12% reduction) in the powder bed, as the finer particles fill in the voids created between the coarser ones. Findings from this study are more »
- Award ID(s):
- Publication Date:
- NSF-PAR ID:
- Journal Name:
- Discrete-Element Simulation of Powder Spreading Process in Binder Jetting, and the Effects of Powder Size
- Sponsoring Org:
- National Science Foundation
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