Extrusion-based additive manufacturing of yttria-partially-stabilized zirconia ceramics

Zirconia-based ceramics have many applications in manufacturing, energy, and biomedical industries due to their excellent properties such as high thermal and oxidation resistance, excellent chemical stability and mechanical strength. Traditional manufacturing processes such as cold pressing, hot pressing, and injection molding have limitations in the fabrication of high-quality zirconia-based ceramics with complex geometries. Additive manufacturing (AM) processes such as binder jetting, photopolymerization, and material extrusion have been recently developed to fabricate complex ceramic parts. However, additive manufacturing of defect-free ceramic parts with superior mechanical properties remains a challenge. To address this issue, a novel extrusion-based AM process was introduced to fabricate yttria-partially-stabilized zirconia ceramics. The mechanical properties such as flexural strength, fracture toughness, compressive strength, hardness, and porosity of the additively manufactured yttria-partially-stabilized zirconia ceramics were characterized. The surface quality and shrinkage of the zirconia parts were also measured. The experimental results have shown that the yttria-partially-stabilized zirconia parts fabricated by the proposed extrusion-based AM process exhibit superior mechanical properties than that of the zirconia parts fabricated by other AM processes.