Paper Number
AC8
Session
Additive Manufacturing and Composites
Title
Embedded 3D printing: Rheology controlled minimum stable feature size
Presentation Date and Time
October 12, 2022 (Wednesday) 1:50
Track / Room
Track 7 / Ontario
Authors
- Hossain, Mohammad Tanver (University of Illinois at Urbana-Champaign, Department of Mechanical Science and Engineering)
- Eom, Wonsik (University of Illinois at Urbana-Champaign, Department of Mechanical Science and Engineering)
- Tawfick, Sameh (University of Illinois at Urbana-Champaign, Department of Mechanical Science and Engineering)
- Ewoldt, Randy H. (University of Illinois at Urbana-Champaign, Mechanical Science and Engineering)
Author and Affiliation Lines
Mohammad Tanver Hossain, Wonsik Eom, Sameh Tawfick and Randy H. Ewoldt
Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801
Speaker / Presenter
Hossain, Mohammad Tanver
Keywords
additive manufacturing
Text of Abstract
Embedded 3D printing has the potential to enable free-form fabrication of complex biological structures that are soft and easily deformable. The morphology of the printed filament in embedded 3D printing is correlated to the rheological properties such as yield stress and interfacial tension of the viscoplastic support gel and the ink material. Particularly, the interfacial tension between the gel and ink materials strongly affects the minimum stable feature size, which can be predicted based on the plasto-capillary length set by the yield stress of the matrix material and the printed ink, and the interfacial tension. For embedded 3D printing, feature sizes are commonly reported around a few hundred microns. Here, we printed a silicone elastomer precursor ink in different viscoplastic matrix materials to understand how the rheology of the gel support affects the printing resolution. Printed diameter, diameter variability, and thread breakup were observed as a function of support gel composition and rheology, extrusion flow rate, tip print speed, and nozzle size. Results are interpreted in the context of the plasto-capillary number. Furthermore, we have successfully printed a stable feature size of around 20 µm in a microgel support without breakup by controlling the rheology of the ink and the matrix material.