%0 Journal Article
%A Giese, Sven
%A Neumeier, Steffen
%A Amberger-Matschkal, Doris
%A Bergholz, Jan
%A Vaßen, Robert
%A Göken, Mathias
%T Microtensile creep testing of freestanding MCrAlY bond coats
%J Journal of materials research
%V 34
%N 15
%@ 2044-5326
%C Cambridge [u.a.]
%I Cambridge Univ. Press
%M FZJ-2019-03601
%P 2643-2652
%D 2019
%X Bond coats are essential in gas turbine technology for oxidation protection. Freestanding MCrAlY (M = Ni, Co) bond coats were investigated with respect to their creep strength at elevated temperatures. Three types of MCrAlY, a Ni-based bond coat Amdry 386, a Co-based bond coat Amdry 9954 and Amdry 9954 + 2 wt% Al2O3 (ODS = oxide dispersion strengthened) produced by low pressure plasma spraying, were analyzed. The two phase microstructure of the bond coats consists of a fcc γ-Ni solid solution and a B2 β-NiAl phase. Constant load experiments were performed in a thermomechanical analyzer at temperatures between 900 and 950 °C. Microtensile test specimens with a diameter of 450 µm were produced by a high-precision grinding and polishing process. Creep rupture was mainly due to void nucleation along the β–γ interfaces and grain boundaries. The time to failure is larger in Ni-based Amdry 386 compared to that in Co-based Amdry 9954 due to a higher fraction of the high-strength β-NiAl phase at test temperatures. The addition of ODS-particles in the Co-based bond coat Amdry 9954 resulted in a better creep resistance but lower ductility in comparison to ODS-particle-free Amdry 9954.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000482958400008
%R 10.1557/jmr.2019.169
%U https://juser.fz-juelich.de/record/863562