Digital light processing of ceria-stabilized zirconia: Role of powder pre-treatment on printability and physico-mechanical properties

In this study, the role of pre-treatment of a ceria-stabilized zirconia powder on slurry printability in Digital Light Processing as well as on density, microstructural features and flexural strength of the sintered materials was investigated. Three powder batches, namely un-milled, ball-milled, and ball-milled and thermally post-treated were compared. Ball-milling induced tetragonal-to-monoclinic phase transformation and the appearance of oxygen vacancies. The thermal post-treatment was effective in restoring a higher tetragonal phase content and the starting cerium oxidation state. Slurries with a fixed solid loading (41 vol%) and variable amounts of dispersant were prepared. Different curing behaviors and, consequently, different qualities of the printed parts were observed. The milled and thermally treated powder was used to produce high-density sintered materials characterized by submicrometric grains (≅ 600 nm) and high flexural strength (≅ 560 MPa).