Fabrication of double-ceramic-layer TBCs by suspension plasma spray
June 24-29, 2018
Rare-earth zirconates, such as La2Zr2O7 and Gd2Zr2O7, have been investigated as one of the candidates for replacing conventional yttria-stabilized zirconia (YSZ) for thermal barrier coating (TBC) applications at higher turbine inlet temperatures. Rare-earth zirconate oxides exhibit little phase transformation upon heating up to melting temperature as well as low thermal conductivity, where as their mechanical properties is inferior to those of YSZ TBCs. Double-ceramic-layer (DCL) TBCs have been investigated in order to take advantage of beneficial characteristics of both YSZ and rare-earth zirconate.
In this study, the fabrication of DCL-TBCs with YSZ layer and rare-earth-zirconate top layer by using suspension plasma spray are reported. Microstructure, compositional profile, thermal conductivity, and thermal durability of DCL-TBCs are characterized. The usefulness of these DCL-TBCs is also discussed.
Seongwon Kim, Soyul Lee, Yoon-Suk Oh, Sung-Min Lee, Hyung-Tae Kim, and Byung-Koog Jang, "Fabrication of double-ceramic-layer TBCs by suspension plasma spray" in "Thermal Barrier Coatings V", Prof. Dr. Robert Vaßen, Forschungszentrum Jülich GmbH, Germany Brian Hazel, Pratt & Whitney, USA Prof. Dr. Uwe Schulz, German Aerospace Center, Germany Dr. Michael J. Maloney, Pratt & Whitney, USA Dr. Ram Darolia, GE Aviation (Retired), USA Eds, ECI Symposium Series, (2018). http://dc.engconfintl.org/tbcv/79