About this Abstract |
| Meeting |
MS&T25: Materials Science & Technology
|
| Symposium
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Alloy Phase Transformations at Elevated Temperatures
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| Presentation Title |
Strengthening Superalloys via Locally Transformed Two-Dimensional Defect Phases |
| Author(s) |
Andreas Bezold, Jan Vollhüter, Lukas Amon, Longsheng Feng, Nicolas Karpstein, Erdmann Spiecker, Yunzhi Wang, Steffen Neumeier, Michael Mills |
| On-Site Speaker (Planned) |
Andreas Bezold |
| Abstract Scope |
Superalloys achieve exceptional high-temperature capabilities through their characteristic two-phase γ/γ’ microstructure. Here, we present an optimized pre-deformation strategy to further refine this microstructure by introducing an extremely high density of two-dimensional defects (about 25 defects per precipitate, which measure around 500 nm in size) into the alloy prior to creep deformation. High-resolution structural and chemical investigations using electron microscopy reveal that these planar defects have locally transformed into ordered hexagonal phases. The introduction of such high defect densities significantly enhances both yield and creep strengths up to 750 °C compared to the undeformed reference state. Detailed electron microscopy investigations are utilized to rationalize the deformation mechanisms with emphasis on dislocation-defect phase interactions. Phase-field simulations are conducted to further rationalize the strengthening effect of the defect phases. Finally, we propose additive manufacturing as an alternative pathway to introduce a high density of locally transformed defect phases to further strengthen 3D-printed alloys. |