Abstract |
3D printed polymer-derived ceramics are an emerging technology designed to overcome challenges associated with ceramic fabrication. However, 3D printing polymer-derived ceramics remains difficult because of challenges encountered during the pyrolysis process, including fracture, warping, and low ceramic yield. Here, a methodology to evaluate post-processing of as-printed vat photopolymerized polymer-derived ceramics, where four different post-processing approaches are examined to potentially improve pyrolysis outcomes is described; as-printed, UV surface flood cure, UV cure followed by a solvent soak to remove unreacted material, and a UV cure followed by intermediate heating to diffuse out unreacted material. Post-processing is introduced to increase cross-linking and eliminate partially reacted oligomers from green bodies to reduce warping and fracture during pyrolysis. After post processing, final ceramic parts showed improved pyrolysis survival and ceramic yield - 97 % and 53 %, respectively. It was demonstrated that utilization of these post-processing methods allowed larger, complex monolithic turbine vanes to be produced. |