Growth kinetics of thermally grown oxide in thermal barrier coatings

Kazuhiro Ogawa, Noritake Gotoh, Tetsuo Shoji

Research output: Chapter in Book/Report/Conference proceedingConference contribution

1 Citation (Scopus)

Abstract

According to several studies, the failure of thermal barrier coatings (TBCs) is induced by thermal stress due to the formation of thermally grown oxide (TGO) at interface between TBC and MCrAlY (M indicates Co, Ni or these combination). Therefore, it is important to investigate high temperature oxidation behavior at the interface. In this work, the TGO at the TBC/MCrAlY interface was characterized in detail. The TBC specimens were thermally aged at 1000 °C to simulate the surface temperature of first rotating blades. After aging, the TGO formed at the interface had two different contrasting layers. One layer was alumina, and the other was a combination of chromium oxide, nickel oxide, cobalt oxide, and spinels (hereafter called mixed oxide). The thickness of the two oxide layers increased with aging time. In order understand oxide formation, specimens with and without TBC were compared using identical substrate and bond coating materials. The TGO thickness of the specimen with TBC was thicker than that without TBC, possibly due to a difference in oxygen potential. These specimens had different oxidation behavior as shown by the extent of oxide growth and the presence of different oxides in the mixed oxide. In case of the specimen with TBC, the mixed oxide consisted of chromium oxide (Cr2O3), nickel oxide (NiO), and cobalt oxide (CoO) that were formed individually. On the other hand, in the case of the specimen without TBC, the mixed oxide mainly consisted of spinels (Ni,Co)(Al,Cr)2O4. The influence of the existence of YSZ top coating for initiation and growth of thermally grown oxide at the TBC/ MCrAlY interface was clarified.

Original languageEnglish
Title of host publicationAdvanced Materials and Processes for Gas Turbines
EditorsG.E. Fuchs, A.W. James, T. Gabb, M. Mclean, H. Harada, G.E. Fuchs, A.W. James, T. Gabb, M. McLean, H. Harada
Pages187-195
Number of pages9
Publication statusPublished - 2002 Dec 1
EventAdvanced Materials and Processes for Gas Turbines - Copper Mountain, CO, United States
Duration: 2002 Sep 222002 Sep 26

Publication series

NameAdvanced Materials and Processes for Gas Turbines

Other

OtherAdvanced Materials and Processes for Gas Turbines
CountryUnited States
CityCopper Mountain, CO
Period02/9/2202/9/26

ASJC Scopus subject areas

  • Engineering(all)
  • Energy Engineering and Power Technology
  • Materials Science(all)

Fingerprint Dive into the research topics of 'Growth kinetics of thermally grown oxide in thermal barrier coatings'. Together they form a unique fingerprint.

Cite this