Interface Oxidation Process of ZrO2-8%Y2O3 / CoNiCrAlY Thermal Barrier Coating System

Article Preview

Abstract:

Thermal barrier coating (TBC) of a gas turbine blade suffers from high temperature oxidation. It is known that thermally growth oxidation (TGO) grows at the interface between ZrO2- 8%Y2O3 and CoNiCrAlY, and the TGO degrades the adhesive strength. The purpose of this study is to clarify the TGO growth process. Thermal aging tests of ZrO2-8%Y2O3 / CoNiCrAlY TBC systems under various temperature conditions were carried out. TGO growth process was observed by an electron probe micro analyzer (EPMA). Both TGO of Al and TGO of other elements were examined, and the thickness of the TGOs were examined. Results are summarized as follows. (1) The delamination occurred at a ZrO2-8%Y2O3 layer beside the interface. (2) The growth rate of complicated TGO which consisted of Co, Ni and Cr increased with an increase of temperature. However, the complicated TGO wasn’t related with the delamination life. (3) The delamination could occur if the thickness of Al TGO increased more than about 3 μm.

You might also be interested in these eBooks

Info:

Periodical:

Key Engineering Materials (Volumes 345-346)

Pages:

1035-1038

Citation:

Online since:

August 2007

Export:

Price:

Permissions CCC:

Permissions PLS:

Сopyright:

© 2007 Trans Tech Publications Ltd. All Rights Reserved

Share:

Citation:

[1] A. G. Evans, M. Y. He and J. W. Hutchinson: Acta Mater., Vol. 45(1997), p.3543.

Google Scholar

[2] Y. Itoh, M. Takahashi, Y. Ishiwatari and K. Nagata: J. Soc. Mat. Sci., Japan, Vol. 47(1998), p.665.

Google Scholar

[3] H. Waki, K. Ogura, I. Nishikawa and Y. Kashihara: JSME Int. J., Ser. A, Vol. 46(2003), p.590.

Google Scholar

[4] M. Arai, U. Iwata, H. Sato, K. Kishimoto: Trans. Jpn. Soc. Mech. Eng. A, Vol. 69(2003), p.245.

Google Scholar

[5] E. P. Busso, J. Lin, S. Sakurai and N. Nakayama: Acta Mater., Vol. 49(2001), p.1515.

Google Scholar