Synergy of solid loading and printability of ceramic paste for optimized properties of alumina via stereolithography-based 3D printing

The challenges associated with stereolithography-based ceramic additive manufacturing using high solid loading pastes are related to the printability of ultrathin layers and complex green bodies without auxiliary support structures directly underneath. In order to develop the strategy of conformal contactless support during additive manufacturing, the printability of alumina ceramic paste with a variety of solid loading, along with mechanical properties of the sintered parts fabricated by stereolithography process was investigated. A combination of scanning electron microscopy, micro-computed tomography scans and three-point bending tests were practiced systematically. The rheological behavior of ceramic paste was regulated distinctly by solid loading. As the solid loading increased, the degree of shrinkage decreased and the relative density increased for the sintered part. The sintered sample from 52 vol% ceramic paste presented the highest flexural strength with well densified microstructure. The research results promote property optimization of ceramic components fabricated by stereolithography method through material compositions and printability of ceramic paste, which simultaneously contributes to perfect support strategy for ceramic additive manufacturing. (C) 2020 The Author(s). Published by Elsevier B.V.