Journal of Thermal Spray Technology

, Volume 10, Issue 3, pp 497–501

Thermal spray yttria-stabilized zirconia phase changes during annealing

  • Jan Ilavsky
  • Jay Wallace
  • Judith K. Stalick
Article

DOI: 10.1361/105996301770349277

Cite this article as:
Ilavsky, J., Wallace, J. & Stalick, J.K. J Therm Spray Tech (2001) 10: 497. doi:10.1361/105996301770349277

Abstract

Phase stability of thermal barrier deposits made from yttria partially stabilized zirconia (Y-PSZ) is a requirement for extended service lifetime. The response of Y-PSZ plasma-sprayed deposits to annealing at 1000, 1200, and 1400 °C with times from 1 to 1000 h has been evaluated using the Rietveld analysis of neutron diffraction data. Results show that the yttria concentration of the as-sprayed tetragonal zirconia component generally decreased with increasing annealing temperature and time. As the yttria content in the tetragonal phase approached a limiting concentration, about 3.5 mol.% of YO1,5, the tetragonal phase transformed into monoclinic phase on cooling. An increase in monoclinic phase content was clearly observed after annealing for 24 h at 1400 °C and was nearly 35% after 100 h at 1400 °C. A similar trend was observed at 1200 °C for longer annealing times, with monoclinic phase formation beginning after 400 h. At 1000 °C, experimental times were not sufficient for monoclinic phase to form, although a decrease in the yttria concentration in the tetragonal phase was observed.

Keywords

neutron scattering phase composition Rietveld analysis yttria-stabilized zirconia 

Copyright information

© ASM International 2001

Authors and Affiliations

  • Jan Ilavsky
    • 1
    • 3
    • 4
  • Jay Wallace
    • 1
  • Judith K. Stalick
    • 2
  1. 1.National Institute of Standards and TechnologyGaithersburg
  2. 2.NIST Center for Neutron ResearchNational Institute of Standards and TechnologyUSA
  3. 3.the University of MarylandCollege Park
  4. 4.the Institute of Plasma PhysicsAcademy of Sciences of the Czech RepublicPragueCzech Republic