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arXiv · 2406.13070

Influence of the coating brittleness on the thermomechanical fatigue behavior of a $\beta$-NiAl coated R125 Ni-based superalloy

Capucine Billard·Damien Texier·Matthieu Rambaudon·Jean-Christophe Teissedre·Noureddine Bourhila·Dimitri Marquie·Lionel Marcin·Hugo Singer·Vincent Maurel
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Abstract

The brittleness of an aluminide diffusion coating protecting a Ren\'e 125 Ni-based polycrystalline superalloy was investigated over a wide range of temperatures in its as-received and thermally aged form. Isothermal and thermal cycled aging were performed on the coated system at a maximum temperature of 1100 {\deg}C. Microstructure evolutions and damage initiation within the coating were characterized. Interrupted tensile tests and thermomechanical fatigue tests were conducted to document critical stress-strain conditions leading to the coating cracking and lifetime for the case of thermo-mechanical fatigue loading. Advanced digital image correlation and acoustic emission techniques were used to detect coating cracking. Isothermal oxidation or cyclic oxidation led to improved strain-to-failure due to metallurgical evolutions and also longer fatigue life under thermomechanical fatigue conditions.

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Capucine Billard, Damien Texier, Matthieu Rambaudon, Jean-Christophe Teissedre, Noureddine Bourhila, Dimitri Marquie, Lionel Marcin, Hugo Singer, Vincent Maurel. 2024-06-18. Influence of the coating brittleness on the thermomechanical fatigue behavior of a $\beta$-NiAl coated R125 Ni-based superalloy. https://arxiv.org/abs/2406.13070

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