Chemical Stability, Structure and Surface Topology of Domestic Comprehensively Stabilized Zirconium Dioxide Ceramics in Simulated Aggressive Environments

Abstract

Subject of the study is the chemical stability of a complex stabilized zirconium dioxide system of 3 mol.% Y2O3 15 mol.% CeO2 in simulated aggressive media (1 and 10% NaOH; 1 and 10% HCl; 1, 10 and 40% CH3COOH.
 The goal – to study the effect of various aggressive media on the structural and chemical stability of domestic comprehensively stabilized zirconium dioxide ceramics under experimental conditions.
 Methods. The tests were carried out on experimental samples of ceramic grinders (40 pcs.) of the same area and shape: the experimental group (20 pcs.) – stabilized zirconium dioxide ceramics, the control group (20 pcs.) – zirconium dioxide ceramics without stabilizing additives. The presence, severity and features of the reaction of zirconium dioxide ceramics to aggressive media were evaluated in a comparative aspect by changing the mass of samples, the microstructure of their surface and the Raman spectra.
 Results. The interaction of complexly stabilized zirconium dioxide with alkaline solutions does not lead to a statistically significant decrease in the mass of samples, under the action of solutions of organic and inorganic acids, a statistically insignificant (p<0.5) increase in total mass is observed. Scanning electron microscopy of ceramic samples of both groups after exposure to aggressive media did not reveal ultrastructural changes in the surface. Raman spectra of light before exposure in aggressive media showed more favorable values of Raman intensity for stabilized zirconium dioxide, which indicates its better degree of crystallization. After exposure to aggressive media, changes in the crystal lattice of the control samples were determined, for stabilized zirconium dioxide, the ratio I260/I320 did not change.
 Conclusions and Relevance. Stabilized zirconium dioxide of the system 3 mol.% Y2O3 15 mol.% CeO2 has increased resistance in aggressive environments, which is of practical importance when choosing a ceramic material for the manufacture of dentures, which are exposed to aggressive biological environments of the oral cavity during the entire service life.