Influence of a grain-locking morphology on properties of doped ZrO2 ceramics made with ultrafine (~ 3 nm) nanoparticles

• Published in: Journal of materials research Vol. 37; no. 23; pp. 4255 - 4267
• Main Authors: Arun, Aditya, Kumar, Kundan, Chowdhury, Anirban
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 14.12.2022; Springer Nature B.V
• Subjects: Applied and Technical Physics; Biomaterials; Ceramics; Chemistry and Materials Science; Density; Hardness; Indentation; Inorganic Chemistry; Locking; Loose powder sintering; Materials Engineering; Materials research; Materials Science; Mechanical properties; Microstructure; Nanoparticles; Nanotechnology; Ultrafines; Yttria-stabilized zirconia; Yttrium oxide; Zirconium dioxide; Phase transformation; Ceramic; Densification; Chemical synthesis; Microstructure; Hardness
• ISSN: 0884-2914; 2044-5326
• DOI: 10.1557/s43578-022-00792-y

The use of ultrafine (~ 3 nm) nanoparticles of 10 mol.% CaO-doped ZrO 2 together with a minimum dwelling time (15 min.) during pressureless sintering yielded high (> 99%)-density ceramic with a unique grain-locking microstructure; no impurity or second phase segregation was observed in the ‘locked’ regions. Although the normal X-ray diffraction data indicated a phase-pure cubic symmetry for the ceramic, Rietveld analysis confirmed a cubic-phase majority (~ 83%) with minor tetragonal content (~ 17%). The microstructure (homogeneously present on both top and interior of ceramics) for the sintered ceramics contributed in achieving high hardness (~ 14 GPa); obtained hardness and indentation toughness values were also comparable to the previously reported cubic ZrO 2  ceramics (doped with Y 2 O 3 ). Considering the high cost of yttria-doped zirconia systems, the suitability with mechanical properties together with high sintered density for the present system suggests its potential usability at larger scales as an alternative to Y 2 O 3 -stabilized zirconia ceramics. Graphical abstract