Effect of Heat Treatment on Structure and Phase Transformation of Rare Earth (Gd) Zirconate

Abstract:

In the present work, zirconium gadolinium oxide (Gd2Zr2O7) ceramics were prepared by annealing in different conditions and with APS (air plasma sprayed) techniques for thermal barrier coating (TBC) application. Thermal properties, phase transformation, crystal structure and cross-sectional morphologies of these materials were investigated. The thermal behaviour of the material was investigated from room temperature to 1500°C using the differential thermal analysis (DTA). The X-ray diffraction methods were used for the qualitative phase analysis. The structure of the studied samples has been characterized by employing powerful Rietveld’s whole X-ray profile fitting technique using the DBWS 9807a program. The SEM and EDS techniques were used to in the ceramic samples morphology analysis and for their chemical composition, respectively. The research showed that further stages of annealing result in the phase transformation of the parent substances and the main phase Gd2Zr2O7. It was found out that complete phase transformation into Gd2Zr2O7 phase takes place only for the air plasma sprayed sample. The analysis of the morphology of the initial powder revealed the spherical shape of the powder particles, which have a porous internal structure.

• Periodical: Solid State Phenomena (Volume 163)
• Pages: 157-160
• DOI: https://doi.org/10.4028/www.scientific.net/SSP.163.157
• Online since: June 2010
• Authors: Grzegorz Moskal, Grzegorz Dercz
• Keywords: APS, Microstructure, Rietveld Analysis, Scanning Electron Microscope (SEM), TBCs, X-Ray Diffraction (XRD), YSZ, Zirconium Gadolinium Oxide

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