High-strength lithography-based additive manufacturing of ceramic components with rapid sintering

Abstract

Additive manufacturing technology enables the fabrication of technical ceramics and multi-materials with unprecedented geometrical accuracy and complexity, opening the path to new functionalities for engineering applications. A crucial step to consolidate 3D-printed ceramic parts is “sintering”, a time and energy (temperature) intensive densification process. Here we present a strategy for rapid sintering (∼ 300–450 °C/min) of lithography-based additively manufactured alumina ceramics enabling consolidation of ceramic components of complex shapes within minutes. Highly dense, fine-grained microstructures were achieved by controlling densification and limiting grain growth through rapid radiation heat transfer. The high mechanical strength and toughness measured in additively manufactured alumina (∼ 810 MPa and ∼ 4.3 MPa m 1/2 ) sintered at 1600 °C within 2 min was superior to that of conventionally sintered reference parts. This study opens the path for rapid sintering of complex shaped ceramic architectures of high density with tailored microstructure and properties. • 3D-printed ceramics with complex geometry can be sintered within minutes. • Rapid radiation using a customized Spark Plasma Sintering system promotes densification. • Controlling the dwell sintering time allows tailoring of grain size in refined microstructures. • Dense and exceptionally high strength 3D-printed alumina were achieved. • Our sintering protocol may be applied to other 3D printed ceramic materials.