Mineralogical and microstructural changes in fused cast Ti-stabilized alumina-zirconia eutectic ceramics at elevated temperatures

Author(s)

Annalena Erlacher, Adrian Villalba Weinberg, Christian Leopold Lengauer, Andreas Börger

Abstract

Ti-stabilized alumina-zirconia eutectic ceramics produced by

fusion-casting are characterized to investigate microstructural

mechanisms at elevated temperatures and to explain the self-sharpening

effect. Scanning electron microscopy (SEM) images show fine-grained

lamellar eutectic microstructures with well-defined domains. After

thermal annealing at 800 °C, distinct cracks formed along the domain

boundaries. Thermal analyses and powder X-ray diffraction (pXRD), using

Rietveld evaluation, confirmed that the cracks are triggered by the

phase transformation from meta-stable tetragonal to monoclinic ZrO₂,

causing a volume increase of up to 13.4 %. This indicates a decrease in

the stabilizing effect of Ti in the meta-stable tetragonal ZrO₂

starting from 669 °C, and subsequently triggering the phase

transformation. Additionally, structural analysis of pXRD data reveals

internal stresses within the crystal lattice, showing expansion of

tetragonal ZrO₂ along the c-axis and distortions in the basal plane in both tetragonal and monoclinic ZrO₂.

Organisation(s)

Department of Mineralogy and Crystallography

External organisation(s)

Imerys Technology Center Austria

Journal

Open Ceramics

Volume

22

Pages

1-8

No. of pages

8

ISSN

2666-5395

DOI

https://doi.org/10.1016/j.oceram.2025.100798

Publication date

06-2025

Peer reviewed

Yes

Austrian Fields of Science 2012

105116 Mineralogy, 105113 Crystallography

Keywords

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