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  • An Experimental Study on the Dynamics of Binder Drops Impacting on a Powder Surface in Binder Jetting Additive Manufacturing
Title: An Experimental Study on the Dynamics of Binder Drops Impacting on a Powder Surface in Binder Jetting Additive Manufacturing
Binder jetting additive manufacturing (AM) is an innovative form of 3D printing that generates complex and advanced structures of various materials by jetting binder drops onto a powder bed. The drops on the bed cure the powder to form structures in a quick and efficient manner. However, the method suffers several flaws including manufacturing inconsistencies and coarse resolution of structures. These flaws may be explained by complex interactions between the binder drop and the powder during the printing process. Therefore, a better understanding of these interactions will be instrumental in the development of binder jetting for fabricating multipurpose, higher quality functional structures. In this study, these complex interactions are analyzed during the impact and subsequent processes. The impact dynamics of binder drops on a powder surface were examined by using a custom impingement rig under various test conditions (i.e., different impact velocities and binder viscosities). A high-speed imaging system was used to capture the transient details of the drop-powder interactions. This study concludes that an increase in drop impact velocity results in a greater range of particle ejection. A lower drop viscosity results in a higher dry spread of particles while a higher drop viscosity results in a greater number of binder-encapsulated particles. Across all cases, binder drops absorb particle granules at a rate inverse to their viscosity.  more » « less
Award ID(s):
2242311
NSF-PAR ID:
10416025
Author(s) / Creator(s):
;
Date Published:
Journal Name:
AIAA SCITECH 2023 Forum
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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