This title appears in the Scientific Report :
2019
Please use the identifier:
http://dx.doi.org/10.1557/jmr.2019.169 in citations.
Microtensile creep testing of freestanding MCrAlY bond coats
Microtensile creep testing of freestanding MCrAlY bond coats
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 9...
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Personal Name(s): | Giese, Sven (Corresponding author) |
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Neumeier, Steffen / Amberger-Matschkal, Doris / Bergholz, Jan / Vaßen, Robert / Göken, Mathias | |
Contributing Institute: |
Werkstoffsynthese und Herstellungsverfahren; IEK-1 |
Published in: | Journal of materials research, 34 (2019) 15, S. 2643-2652 |
Imprint: |
Cambridge [u.a.]
Cambridge Univ. Press
2019
|
DOI: |
10.1557/jmr.2019.169 |
Document Type: |
Journal Article |
Research Program: |
Methods and Concepts for Material Development |
Publikationsportal JuSER |
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. |