About this Abstract |
| Meeting |
2026 TMS Annual Meeting & Exhibition
|
| Symposium
|
Dilute Alloying and Impurity Effects on Phase Transformations
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| Presentation Title |
Anomalous High Temperature Behavior of Near-Equiatomic FeNi Alloys With Dilute Phosphorus Additions |
| Author(s) |
Ugochukwu Philip Ochieze, Zachary Miller, Matthew A. Steiner |
| On-Site Speaker (Planned) |
Matthew A. Steiner |
| Abstract Scope |
While the equilibrium phase diagram of Fe-Ni is well established due to unique behavior around the 36% Ni “Invar” composition, the effects of non-metal impurities have received less attention because of their typically deleterious impact on Invar-type properties. Understanding the impact of dilute (< 1at%) P additions on the equilibria and phase transformations of the Fe-Ni system is important, however, to developing processing routes for Fe-Ni-P magnetic materials, a potential replacement for rare-earth permanent magnets. Highly anomalous dilatation behavior of Fe-Ni-0.5%P alloys is observed near 900°C, hypothesized to be related to ordering of the phosphorus impurities as the rapidity of the transformation is inconsistent with long-range diffusion. The effect is most prominent at equiatomic compositions, suggesting an interplay with Fe-Ni local chemical ordering that may impact the kinetics of L10 ordered Fe-Ni meteoric phases (known to have P precipitates) that are notoriously difficult to reproduce terrestrially. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Phase Transformations, Magnetic Materials, |