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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
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Highly thermal-stable ferromagnetism by a natural composite
Tianyu Ma1,2, Junming Gou1, Shanshan Hu1
1School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Key Laboratory of Novel Materials for Information Technology of Zhejiang Province, Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310027, China.
Nature Communications
|January 19, 2017
Summary
This study reveals that Fe-Ga alloys maintain stable magnetization and magnetostriction up to their Curie temperature. This unusual thermal stability is due to a dual-magnetic-phase transformation, offering potential for advanced magnetic materials.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- Ferromagnetic materials typically lose magnetic properties with increasing temperature due to declining magnetic order near the Curie temperature (TC).
- Maintaining stable magnetism at elevated temperatures is a significant technological challenge.
Purpose of the Study:
- To investigate the thermal stability of magnetic properties in Fe-Ga alloys.
- To understand the underlying mechanisms responsible for unusual thermal stability in magnetic materials.
Main Methods:
- Experimental characterization of magnetization and magnetostriction as a function of temperature.
- Analysis of structural and magnetic phase transitions.
Main Results:
- Fe-Ga alloys demonstrate highly thermal-stable magnetization up to 880 K, near their TC.
- Magnetostriction remains largely unchanged over a broad temperature range.
- The observed stability is attributed to a dual-magnetic-phase nature and a gradual transformation between phases.
Conclusions:
- Fe-Ga alloys exhibit exceptional thermal stability of magnetic properties, defying conventional ferromagnetism behavior.
- The dual-magnetic-phase transformation mechanism offers a pathway for developing robust ferromagnetic and magnetostrictive materials for high-temperature applications.
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