Microtensile creep testing of freestanding MCrAlY bond coats

Giese S, Neumeier S, Amberger-Matschkal D, Bergholz J, Vaßen R, Göken M (2019)

Publication Type: Journal article

Publication year: 2019

Journal

Journal of Materials Research Cambridge University Press

DOI: 10.1557/jmr.2019.169

Abstract

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-γinterfaces 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.

Authors with CRIS profile

Sven Giese Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Steffen Neumeier Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften) Mathias Göken Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Additional Organisation(s)

Lehrstuhl für Werkstoffwissenschaften (Allgemeine Werkstoffeigenschaften)

Related research project(s)

Nanomechanical and nanometrological characterisation of single-crystalline Ni-base superalloys (A06) (SFB/TRR 103) TRR 103: Vom Atom zur Turbinenschaufel - wissenschaftliche Grundlagen für eine neue Generation einkristalliner Superlegierungen Jan. 1, 2012 - Dec. 31, 2015

Involved external institutions

Forschungszentrum Jülich / Research Centre Jülich (FZJ) DE Germany (DE)

How to cite

APA:

Giese, S., Neumeier, S., Amberger-Matschkal, D., Bergholz, J., Vaßen, R., & Göken, M. (2019). Microtensile creep testing of freestanding MCrAlY bond coats. Journal of Materials Research. https://dx.doi.org/10.1557/jmr.2019.169

MLA:

Giese, Sven, et al. "Microtensile creep testing of freestanding MCrAlY bond coats." Journal of Materials Research (2019).

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