About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
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Advances in Magnetic Materials
|
Presentation Title |
Mixed Magnetic Phases in AlxCoCrNiFe High Entropy Alloy |
Author(s) |
Cameron Jorgensen, Louis Santodonato, Namila Liyanage, Lizabeth Quigley, Peter Liaw, Dustin Gilbert, Lisa Debeer-Schmitt, Raymond R Unocic |
On-Site Speaker (Planned) |
Cameron Jorgensen |
Abstract Scope |
The distribution in atomic sizes and masses in high-entropy alloys results in extreme local environments, which manifests in the thermal and magnetic properties. In this work, high-entropy alloys of (Fe,Co,Cr,Ni)Alx, x ≤ 2, and their temperature-dependent magnetic and electronic properties are determined. Magnetometry results show all the samples are ferromagnetic, with a high-temperature phase, TC >200 K, and a second low-temperature phase with TC≈20 K. However, the high-temperature phase is not associated with an open hysteresis loop, suggesting superparamagnetic behavior. The closed hysteresis loop suggests the ferromagnetism appears as small clusters, a theory explored with small-angle neutron scattering (SANS). SANS confirms soft ferromagnetic properties with alignment occurring with as little as 0.25 T in some samples as well as smaller features that likely are associated with chromium frustrations localized in a matrix of Al, Ni, and Fe. At T<10 K there is a downturn in magnetization due to antiferromagnetic phases. |
Proceedings Inclusion? |
Planned: |
Keywords |
High-Entropy Alloys, Magnetic Materials, |