Subsolidus Equilibria And Stabilization Of Tetragonal ZrO2 In The System ZrO2‐Al2O3‐SiO2

Author

Charles A. Sorrell, Missouri University of Science and Technology

Abstract

The irreversible reaction between zircon and alumina to form mullite and zirconia was observed to proceed very slowly at 1480°C, confirming the existence of a stable join between mullite and zirconia in addition to the join between mullite and zircon. Attempts to determine equilibrium assemblages in powder samples of several combinations of the constituents at 1300° and 1400°C were unsuccessful. Metastable tetragonal ZrO₂ was observed in fired powder samples containing kaolinite, in fired zircon‐alumina samples, and in calcined gels prepared from zirconyl nitrate, aluminum nitrate, and colloidal silica in water. Tetragonal ZrO₂ was the dominant crystalline phase in gels fired for 24 h at 800°, 950°, and 1100°C; the thermal stability of the phase was enhanced by Al₂O₃ and by SiO₂, but most effectively by mixtures of the two. Line broadening measurements and electron microscope observation indicate that the tetragonal ZrO₂, with apparent crystallite sizes between 0.009 and 0.1 μm, develops as an intergrowth with, and is stabilized by, the amorphous matrix of Al₂O₃ and SiO₂. Copyright © 1977, Wiley Blackwell. All rights reserved

Recommended Citation

C. A. Sorrell, "Subsolidus Equilibria And Stabilization Of Tetragonal ZrO2 In The System ZrO2‐Al2O3‐SiO2," Journal of the American Ceramic Society, vol. 60, no. 11 thru 12, pp. 495 - 499, Wiley, Jan 1977.

The definitive version is available at https://doi.org/10.1111/j.1151-2916.1977.tb14090.x

Department(s)

Materials Science and Engineering

Publication Status

Full Access

International Standard Serial Number (ISSN)

1551-2916; 0002-7820

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2023 Wiley, All rights reserved.

Publication Date

01 Jan 1977