Publication detail

Thermal cycling damage in pre-oxidized plasma-sprayed MCrAlY plus YSZ thermal barrier coatings: Phenomenon of multiple parallel delamination of the TGO layer

SLÁMEČKA, K. JECH, D. KLAKURKOVÁ, L. TKACHENKO, S. REMEŠOVÁ, M. GEJDOŠ, P. ČELKO, L.

Original Title

Thermal cycling damage in pre-oxidized plasma-sprayed MCrAlY plus YSZ thermal barrier coatings: Phenomenon of multiple parallel delamination of the TGO layer

Type

journal article in Web of Science

Language

English

Original Abstract

This paper focuses on thermal cycling failure of pre-oxidized plasma-sprayed thermal barrier coatings (TBCs) with NiCrAlY and NiCoCrAlY bond-coats and yttria-stabilized zirconia (YSZ) top-coats. Pre-oxidation of full NiCrAlY + YSZ and NiCoCrAlY + YSZ TBC systems to the thickness of the thermally grown oxide (TGO) of similar to 3 mu m was carried out mainly to reduce the influence of initial residual stresses related to the plasma spraying process. The NiCoCrAlY coatings were found to be rougher than the NiCrAlY coatings, the arithmetic average roughness S-a being nearly two times higher and the relative surface area R-s being, respectively, similar to 1.8 and similar to 1.5 for the as-sprayed coatings. It was interesting to observe that despite much greater roughness of its bond-coat, the thermal cycling life of NiCoCrAlY + YSZ TBC system was more than a factor of two shorter when cycled at 1050 degrees C and still only comparable when cycled at 1150 degrees C. This resulted from much larger portion of the interface being influenced by repeated delamination of the TGO layer from the bond-coat, which formed multiple parallel alumina fragments of similar thickness. Most likely, the major cause for such behaviour was the higher thermal expansion of the NiCoCrAlY bond-coat and its higher oxidation rate, although the effect of the interfacial geometry certainly cannot be excluded.

Keywords

Thermal barrier coatings (TBCs); Plasma spray; Bond-coat roughness; Thermal cycling; Oxidation

Authors

SLÁMEČKA, K.; JECH, D.; KLAKURKOVÁ, L.; TKACHENKO, S.; REMEŠOVÁ, M.; GEJDOŠ, P.; ČELKO, L.

Released

25. 2. 2020

Publisher

ELSEVIER SCIENCE SA

Location

LAUSANNE

ISBN

0257-8972

Periodical

Surface and Coatings Technology

Year of study

384

Number

125328

State

Swiss Confederation

Pages from

1

Pages to

13

Pages count

13

URL

https://reader.elsevier.com/reader/sd/pii/S0257897219313180?token=F43EF3142DCE39A8B02A032B270D255796DA7A6BA5646D64A687144444FEC7A9EEFFFE1EC2B229987240C8C431F5BB1D

BibTex

@article{BUT164050,
  author="Karel {Slámečka} and David {Jech} and Lenka {Klakurková} and Serhii {Tkachenko} and Michaela {Remešová} and Pavel {Gejdoš} and Ladislav {Čelko}",
  title="Thermal cycling damage in pre-oxidized plasma-sprayed MCrAlY plus YSZ thermal barrier coatings: Phenomenon of multiple parallel delamination of the TGO layer",
  journal="Surface and Coatings Technology",
  year="2020",
  volume="384",
  number="125328",
  pages="1--13",
  doi="10.1016/j.surfcoat.2019.125328",
  issn="0257-8972",
  url="https://reader.elsevier.com/reader/sd/pii/S0257897219313180?token=F43EF3142DCE39A8B02A032B270D255796DA7A6BA5646D64A687144444FEC7A9EEFFFE1EC2B229987240C8C431F5BB1D"
}