Influence of sintering atmosphere on the formation of ZrSiO₄ by solid-state sintering method

Exploring the influence of sintering atmosphere on the formation of ZrSiO4 is of great significance. Herein, ZrSiO4 ceramics were prepared by the solid-state reactive sintering method under different atmospheres (air, N-2, vacuum, and Ar + 5%H-2). The influence of sintering atmosphere on the phase and microstructure evolutions of the obtained ceramics was investigated. It was found that ZrSiO4 ceramics could be prepared under air atmosphere, whereas ZrO2-SiO2 glass ceramics were obtained under N-2, vacuum, and Ar + 5%H-2 atmosphere, which may be due to the fact that the oxygen-deficient environment inhibits the transformation of ZrO2 to tetragonal phase (t-ZrO2) and the crystallization of amorphous SiO2. The results demonstrated that t-ZrO2 and c-SiO2 were beneficial for the formation of ZrSiO4. The ZrSiO4 conversion fraction was up to 96.16% under air atmosphere at 1450 degrees C for 6 h. Furthermore, the predominant formation mechanism of ZrSiO4 was the reaction between t-ZrO2 and c-SiO2.