About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
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Symposium
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Deformation Mechanisms, Microstructure Evolution, and Mechanical Properties of Nanoscale Materials
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Presentation Title |
First Principles Study of Local Phase Transformation in Ni Base Superalloys
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Author(s) |
Maryam Ghazisaeidi, Naga Sri Harsha Gunda, Michael Mills |
On-Site Speaker (Planned) |
Maryam Ghazisaeidi |
Abstract Scope |
The segregation or depletion of solutes to or from the stacking fault region changes the SFE and further influences dislocation behavior. In the complex composition space of Ni-base superalloys, the segregation of solutes to stacking faults has been shown to bring about the formation of local phases. In other words, a first-order “segregation transition” can occur at the defects when the bulk alloy composition and temperature are in a single-phase range. We use first-principles calculations to systematically study the formation of local phases at superlattice faults. Specifically, we investigate the effect of Nb, Co, and Ti concentrations on the formation of various local phases. In addition, we study the effect of these phases on the subsequent deformation mechanisms. Our results can be used to find an optimized composition, at which the beneficial strengthening effect of local phases can be achieved without precipitation of potentially deleterious phases. |
Proceedings Inclusion? |
Planned: |
Keywords |
Computational Materials Science & Engineering, Phase Transformations, Mechanical Properties |