About this Abstract |
| Meeting |
11th International Symposium on Superalloy 718 and Derivatives 2026: Legacy, Innovations, and Future Directions
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| Symposium
|
Superalloy 718 and Derivatives 2026: Legacy, Innovations, and Future Directions
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| Presentation Title |
Investigating Hydrogen Embrittlement in Novel High-Strength Ni-Based Superalloys Based on IN725 |
| Author(s) |
Stoichko Antonov, Yuan Tian, Chris San Marchi, Paul D Jablonski, Martin Detrois |
| On-Site Speaker (Planned) |
Stoichko Antonov |
| Abstract Scope |
The resistance of a novel high-strength Ni-based superalloy variants (based on IN725) to hydrogen embrittlement was investigated using room temperature tension testing after gaseous charging in pure hydrogen as well as creep testing with flowing H2/Ar gas mixture. The composition of the alloy was varied using different Ti/Al ratios and low/high Ta concentration to promote the formation of various phases and morphologies, e.g. preferential formation of γ′ or γ″ precipitates. Thus, different bulk co-precipitation of compact and sandwich structured precipitate strengthening phases were formed, but most importantly, various grain boundary phase precipitates. It was found that the grain boundary precipitates play a dominant role to the embrittlement of the material and intergranular fracture was most common. An alternate aging heat treatment was also investigated to try and minimize the effect of the grain boundary phases, by suppressing certain phase formation, while maintaining the high strength conferred by the intragranular structure. Besides mechanical performance, scanning electron microscopy, electron dispersive spectroscopy, thermal desorption mass spectrometry and atom probe tomography were employed to understand the effects of various microstructural features on the resistance to hydrogen embrittlement. The findings offer insights and design pathways for the development of high-strength Ni-based superalloys capable of operate in hydrogen-rich environments and can be applied to a wide range of alloys in the 718 and derivative family. |
| Proceedings Inclusion? |
Definite: At-meeting proceedings |