3D Printing of Unsupported Multi-Scale and Large-Span Ceramic via Near-Infrared Assisted Direct Ink Writing

Abstract

Auxiliary supports are commonly introduced to avoid collapse in three-dimensional (3D) ceramic printing with low-angle structures, which could bring concerns of complex process and unsatisfying material utilization, limiting the improvements of printing efficiency. To overcome this limitation, this paper presents a simple ceramic printing method, which realizes printing of unsupported multi-scale and large-span ceramics through the combination of direct ink writing (DIW) and up-conversion particles-assisted photopolymerization (UCAP) process under near-infrared (NIR) irradiation. This printing technology enables in-situ curing of multi-scale filaments with diameters ranging from 410 µm to 3.50 mm, and successfully constructed ceramic structures of torsion spring, three-dimensional bending and cantilever beam through unsupported printing. This method will bring more innovation space to the high-throughput and unsupported 3D manufacturing of complex shape ceramics.