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Fabrication and Characterization of Ceramics and Thermal Barrier Coatings of Lanthanum Zirconate with Reduced Rare-earth Contents in the La2O2-ZrO2 System

희토류 저감형 란타눔 지르코네이트(La2O2-ZrO2계) 세라믹스와 열차폐코팅의 제조 및 특성평가

  • Received : 2015.10.26
  • Accepted : 2015.12.01
  • Published : 2015.12.28

Abstract

Lanthanum zirconate, $La_2Zr_2O_7$, is one of the most promising candidates for next-generation thermal barrier coating (TBC) applications in high efficient gas turbines due to its low thermal conductivity and chemical stability at high temperature. In this study, bulk specimens and thermal barrier coatings are fabricated via a variety of sintering processes as well as suspension plasma spray in lanthanum zirconates with reduced rare-earth contents. The phase formation, microstructure, and thermo-physical properties of these oxide ceramics and coatings are examined. In particular, lanthanum zirconates with reduced rare-earth contents in a $La_2Zr_2O_7-4YSZ$ composite system exhibit a single phase of fluorite or pyrochlore after fabricated by suspension plasma spray or spark plasma sintering. The potential of lanthanum zirconate ceramics for TBC applications is also discussed.

Keywords

Thermal barrier coatings(TBCs);Suspension plasma spray;Lanthanum zirconate;Phase formation;Thermophysical properties

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Cited by

  1. Phase Formation and Thermo-physical Properties of Lanthanum/Gadolinium Zirconate with Reduced Rare-earth Contents for Thermal Barrier Coatings vol.22, pp.6, 2015, https://doi.org/10.4150/KPMI.2015.22.6.420

Acknowledgement

Grant : 고효율 발전을 위한 1600°C급 가스터빈 소재 개발