Thermodynamic analysis of the cubic-tetragonal phase equilibria in the system ZrO{sub 2}-YO{sub 1.5}

Journal Article · Wed Oct 01 04:00:00 EDT 1997 · Journal of the American Ceramic Society

OSTI ID:554067

Katamura, Junji; Sakuma, Taketo ^[1]

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1. Univ. of Tokyo (Japan). Dept. of Materials Science

The cubic-tetragonal (c-t) phase equilibria in the system ZrO{sub 2}-YO{sub 1.5} are thermodynamically analyzed from Landau`s phenomenological theory. The calculated c-t two-phase field is depicted as a miscibility gap with a sharp maximum and the spinodal region as originally predicted by Hillert and Sakuma. However, the observed c-t two-phase field and the spinodal region are better described by the present model. In addition, this model can be used to discuss the nature of the c-t diffusionless transformation from the order parameter in contrast with the original model. The predicted change in the tetragonality of t-ZrO{sub 2} with YO{sub 1.5} content is slightly different from that in the cla axial ratio estimated from X-ray diffraction analysis. The displacement of cations and anions may not take place simultaneously during the c-t transformation.

• OSTI ID: 554067
• Journal Information: Journal of the American Ceramic Society, Journal Name: Journal of the American Ceramic Society Journal Issue: 10 Vol. 80; ISSN 0002-7820; ISSN JACTAW
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CRYSTAL-PHASE TRANSFORMATIONS
CUBIC LATTICES
EQUILIBRIUM
PHASE STUDIES
TETRAGONAL LATTICES
THERMODYNAMIC MODEL
YTTRIUM OXIDES
ZIRCONIUM OXIDES