High-temperature phase stability of Y2O3 and SiO2 co-doped ZrO2 powder

Y2O3 and SiO2 co-doped ZrO2 powders with various additions of SiO2 substitution Y2O3 have been prepared by co-precipitation method. The microstructure, phase and chemical composition, phase transformation process, and phase stability after repeated calcination at 1300 degrees C of these powders have been investigated. The main phase of all powders is t '-ZrO2. There is no phase transformation when the powders are heated from room temperature to 1400 degrees C. Increasing the ratio (1:4 to 4:1) of SiO2 substitution Y2O3 will reduce the tetragonality of the powder at 1300 degrees C. The amorphous SiO2 will inhibit the growth of grains to a certain extent during the calcination process. The increase of the substitution ratio of SiO2 for Y2O3 will lead to the m-ZrO2 more stable and the t '-ZrO2 more unstable. The relationship among the SiO2 substitution Y2O3 addition, phase composition, and high-temperature phase stability of the powders has been discussed. [GRAPHICS] .

Automated summary

Y2O3 and SiO2 co-doped ZrO2 powders were prepared by co-precipitation method, and the microstructure, phase transformation process, and phase stability were investigated. The results show that increasing the substitution ratio of SiO2 for Y2O3 reduces the tetragonality of the powder and inhibits grain growth.