| Abstract Scope |
Fabrication of dense ceramic parts with complex geometries by extrusion-based additive manufacturing processes is challenging due to the paste’s non-Newtonian behavior, compressibility, and inhomogeneity and the required precise control of the extrusion start and stop to dispense the paste on demand. We have developed an extrusion-based additive manufacturing process, called Ceramic On-Demand Extrusion (CODE), for fabricating highly dense ceramic components from aqueous, high-solids-loading pastes. Afterwards, the fabricated parts are dried in a humidity-controlled chamber and then sintered under atmospheric conditions. The mechanical properties of sintered samples were compared to those from conventional manufacturing processes and other ceramic additive manufacturing processes. Also investigated were sacrificial materials used to build support structures for fabricating complex ceramic components with overhangs, cooling channels, etc. For fabricating parts with functionally graded materials, a dynamic mixer and an extrusion control scheme were developed for fabricating parts with material compositions graded in real time. |