Characterization and Densification of Hot Pressed ZrCN–ZrO2 Ceramics

Abstract

ZrCN-ZrO2 ceramics were produced by hot pressing at a temperature of 2273 K, a pressure of 30 MPa, and a holding time at a given temperature of 15 minutes. Sintering was carried out in a vacuum environment. High-density ZrCN-ZrO2 ceramics were manufactured using zirconium nitride and carbide powders. Zirconium dioxide acted as a sintering additive due to its lowest melting point among the studied compounds. Using scanning electron microscopy and X-ray phase analysis, the presence of zirconium carbonitride as a matrix phase with different stoichiometry, depending on the change in the initial composition of the powders, was established. An increase in strength, hardness, Young's modulus, and crack resistance of the studied materials was observed with an increase in the content of zirconium nitride in the mixture of initial powders and a decrease in the porosity of the material. At the same time, a decrease in subgrains was recorded according to the results of X-ray phase analysis.