Tetragonal Phase in the System ZrO2-Y2O3

Abstract

Precipitates of the high-ZrO2 tetragonal distorted-fluorite phase in the system ZrO2-Y2O3 appear to be quite different from those observed in other well-studied partially stabilized zirconias (Mg-PSZ). In this paper, we discuss the nature of the tetragonal phase in Y2O3 partially stabilized zirconia (Y-PSZ) single crystals. We note that three versions of the phase diagram exist, which differ in detail mainly at the high-ZrO2 region; our work thus also sheds light on the subsolidus phase equilibria in this system. Scott 4 described a metastable 'nontransformable' high-Y2O3-content tetragonal ZrO2 solid solution (t-ZrO2), which he and other workers suggested formed from the cubic ZrO2 solid solution (c-ZrO2) via a displacive phase transformation; the nontransformability relates to its reluctance to undergo the stress-assisted martensitic transformation to monoclinic symmetry found in lower-Y2-O3-content t-ZrO2. (JES)

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Document Details

Document Type
Technical Report
Publication Date
Jan 01, 1985
Accession Number
ADA224505

Entities

People

  • A. H. Heuer
  • T. E. Mitchell
  • V. Lanteri

Organizations

  • Case Western Reserve University

Tags

Communities of Interest

  • Air Platforms

DTIC Thesaurus Topics

  • Critical Temperature
  • Crystals
  • Diffraction
  • Electron Microscopy
  • Energy
  • Free Energy
  • Heat Treatment
  • High Temperature
  • Materials
  • Materials Science
  • Microstructure
  • Phase Diagrams
  • Phase Transformations
  • Single Crystals
  • Solid Solutions
  • X Rays
  • X-Ray Diffraction

Fields of Study

  • Materials science

Readers

  • Materials Science and Engineering.
  • Powder metallurgy of Titanium alloys.
  • Theoretical Analysis.