Additive Manufacturing of Alumina Components by Extrusion of UV-Curable Pastes

Lok-kun Tsui1, Erin Maines2, Lindsey Evans2, David Keicher3, Judith Lavin2

  1. University of New Mexico
  2. Sandia National Laboratories
  3. Integrated Deposition Solutions, Inc

Additive manufacturing of ceramic materials is an attractive technique for rapid prototyping of components at small scales and low cost. We have investigated the printing of alumina pastes loaded at 70-81.5 wt% solids in a UV curable resin and deposited by extrusion from a syringe head on a Hyrel System 30M printer. The print head is equipped with an array of UV LEDs, which solidify the paste without the need for any applied heating or cooling. This technique allows for the deposition of high solids-loading pastes in small quantities under ambient temperature conditions. Parameters optimized include print speed, layer height, applied force, and deposition rate. Using A15 alumina and submicron A16 powder precursors, we can achieve bulk densities of 91% and 96% of theoretical density respectively. The internal defect microstructure of the printed samples is evaluated using x-ray computed tomography. The influence of dispersants and surfactants added to the powder on the rheology of the pastes, the print process parameters, and the quality of the final components are also investigated.

Sandia National Laboratories is a multi-mission laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy’s National Nuclear Security Administration under contract DE-NA0003525.