Published July 8, 2009 | Version v1
Journal article

Effects of Y2O3 addition on the phase evolution and thermophysical properties of lanthanum zirconate

  • 1. Beijing Institute of Aeronautical Materials, Department 5, P.O. Box 81-5, Beijing 100095 (China)
  • 2. Graduate School of Chinese Academy of Sciences, Beijing 100039 (China)
  • 3. State Key Laboratory of Rare Earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022 (China)

Description

Lanthanum zirconate (La2Zr2O7, LZ) powders with the addition of various Y2O3 contents for potential thermal barrier coatings (TBCs) application were synthesized by solid-state reaction. The structure evolution, sintering-resistance and thermophysical properties of the synthesized powders and sintered ceramics were systematically studied. X-ray diffraction (XRD) results indicate that LZ containing 3-12 wt.% Y2O3 mainly keeps a pyrochlore-type structure, and two new phases of LaYO3 and Y0.18Zr0.82O1.91 are also detected. Raman spectra confirm that the higher the Y2O3 content, the easier is the formation of LaYO3. With the increase of Y2O3 content, the linear thermal expansion coefficients (TEC) of different La2O3-ZrO2-Y2O3 ceramics may gradually decrease. Additionally, LZ ceramics doped with 3 wt.% Y2O3 have the lowest relative density and the highest sintering-resistance among all samples, implying that it is the best candidate for TBCs among those samples in this investigation.

Availability note (English)

Available from http://dx.doi.org/10.1016/j.jallcom.2009.02.048

Additional details

Identifiers

DOI
10.1016/j.jallcom.2009.02.048;
PII
S0925-8388(09)00335-1;

Publishing Information

Journal Title
Journal of Alloys and Compounds
Journal Volume
480
Journal Issue
2
Journal Page Range
p. 220-224
ISSN
0925-8388
CODEN
JALCEU

Optional Information

Copyright
Copyright (c) 2009 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.