| About this Abstract |
| Meeting |
2025 TMS Annual Meeting & Exhibition
|
| Symposium
|
Additive Manufacturing and Innovative Powder/Wire Processing of Multifunctional Materials
|
| Presentation Title |
Impact of Magnetic, Atomic and Microstructural Ordering on the Magnetocaloric Performance of Powdered NiCoMnSn Metamagnetic Shape Memory Ribbons |
| Author(s) |
Jose Maria Porro, Bosco Rodriguez-Crespo, Natalia Rio-Lopez, Patricia Lazpita, Santiago Ceballos, Mariana Rios, Daniel Domenech, Jose Alberto Rodriguez-Velamazan, Javier Lopez-Garcia, Volodymyr Chernenko, Daniel Salazar |
| On-Site Speaker (Planned) |
Jose Maria Porro |
| Abstract Scope |
Co-doped NiMnSn Heusler-type metamagnetic shape memory alloys (MMSMAs) are promising materials for the next-generation solid-state refrigeration systems. Mn-rich NiCoMnSn powders were obtained from their ribbon form minimizing residual stresses, defects and disorder in the microstructure. Since atomic order and crystallographic structure are crucial in the transformation and magnetic properties, a structural analysis of the powders after different heat treatments was performed by neutron diffraction. The austenite of the non-heat-treated powder exhibits a highly stressed structure, leading to an incomplete martensitic transformation and coexistence of martensite and austenite at low temperatures. Magnetic structure of the austenite was also determined by neutron diffraction, obtaining a ferromagnetic coupling between 4a and 4b Wyckoff positions. A heat treatment facilitates the transformation and enables the formation of a pure martensite. A fully completed structural transformation leads to a significant increase of the magnetisation change across the martensitic transformation and to high values of refrigeration capacity. |
| Proceedings Inclusion? |
Planned: |
| Keywords |
Magnetic Materials, Additive Manufacturing, |