• Wang, Kaiyang
• Xu, Artemis
• Matia, Yoav
• Liu, Zheng
• Mengüç, Yiğit
• Wallin, Thomas
• Darkesburkey, Cameron
• Barreiros, Jose A.
• Pan, Wenyang
• Giannelis, Emmanuel P.

Abstract

<jats:title>Abstract</jats:title><jats:p>An acoustic liquefaction approach to enhance the flow of yield stress fluids during Digital Light Processing (DLP)‐based 3D printing is reported. This enhanced flow enables processing of ultrahigh‐viscosity resins (μ<jats:sub>app</jats:sub> &gt; 3700 Pa s at shear rates  = 0.01 s<jats:sup>–1</jats:sup>) based on silica particles in a silicone photopolymer. Numerical simulations of the acousto–mechanical coupling in the DLP resin feed system at different agitation frequencies predict local resin flow velocities exceeding 100 mm s<jats:sup>–1</jats:sup> at acoustic transduction frequencies of 110 s<jats:sup>–1</jats:sup>. Under these conditions, highly loaded particle suspensions (weight fractions, ϕ = 0.23) can be printed successfully in complex geometries. Such mechanically reinforced composites possess a tensile toughness 2000% greater than the neat photopolymer. Beyond an increase in processible viscosities, acoustophoretic liquefaction DLP (AL‐DLP) creates a transient reduction in apparent viscosity that promotes resin recirculation and decreases viscous adhesion. As a result, acoustophoretic liquefaction Digital Light Processing (AL‐DLP) improves the printed feature resolution by more than 25%, increases printable object sizes by over 50 times, and can build parts &gt;3 × faster when compared to conventional methodologies.</jats:p>

Topics

• nanoparticle
• impedance spectroscopy
• simulation
• composite
• viscosity
• resin