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

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216305%3A26620%2F20%3APU136550" target="_blank" >RIV/00216305:26620/20:PU136550 - isvavai.cz</a>

Result on the web

<a href="https://reader.elsevier.com/reader/sd/pii/S0257897219313180?token=F43EF3142DCE39A8B02A032B270D255796DA7A6BA5646D64A687144444FEC7A9EEFFFE1EC2B229987240C8C431F5BB1D" target="_blank" >https://reader.elsevier.com/reader/sd/pii/S0257897219313180?token=F43EF3142DCE39A8B02A032B270D255796DA7A6BA5646D64A687144444FEC7A9EEFFFE1EC2B229987240C8C431F5BB1D</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.surfcoat.2019.125328" target="_blank" >10.1016/j.surfcoat.2019.125328</a>

Result language

angličtina

Original language name

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

Original language description

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.

Czech name

—

Czech description

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Type

J_imp - Article in a specialist periodical, which is included in the Web of Science database

CEP classification

—

OECD FORD branch

20506 - Coating and films

Project

Result was created during the realization of more than one project. More information in the Projects tab.

Continuities

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Publication year

2020

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Surface and Coatings Technology

ISSN

0257-8972

e-ISSN

—

Volume of the periodical

384

Issue of the periodical within the volume

125328

Country of publishing house

CH - SWITZERLAND

Number of pages

13

Pages from-to

1-13

UT code for WoS article

000515200000030

EID of the result in the Scopus database

2-s2.0-85077501009