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Correlation Between the Magnetic Properties of Ce-Containing Magnets and the CeFe2 Phase at Various Sintering
Qingpeng Shen1,2,3, Munan Yang2,3,4, Ihor Bulyk1
1School of Materials Science and Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China.
Materials (Basel, Switzerland)
|November 27, 2024
Summary
Sintering temperature significantly impacts magnet properties by influencing the CeFe2 phase. Higher temperatures improve magnetic properties like remanence and coercivity by enhancing grain boundary fluidity and reducing defects.
Area of Science:
- Materials Science
- Magnetism
- Metallurgy
Background:
- The magnetic properties of rare-earth magnets are critically dependent on their microstructure and phase composition.
- Understanding the role of the CeFe2 phase and grain boundary behavior during sintering is crucial for optimizing magnet performance.
Purpose of the Study:
- To investigate the correlation between sintering temperature, CeFe2 phase content and distribution, and the resulting magnetic properties of magnets.
- To elucidate the microstructural evolution and its impact on remanence and coercivity.
Main Methods:
- Magnets were sintered at various temperatures to control phase formation and microstructure.
- Magnetic properties, including remanence and coercivity, were measured.
- Phase analysis focused on the CeFe2 and Ce2Fe17 phases and their distribution.
Main Results:
- Lower sintering temperatures result in poor grain boundary phase flow and increased defects, leading to inferior magnetic properties.
- Increasing sintering temperature enhances the CeFe2 phase ratio, improving fluidity and filling defects, thus increasing remanence.
- Elevated temperatures also increase grain size, which can negatively affect coercivity, while optimal coercivity was achieved at 1080 °C due to optimized grain boundary phase.
Conclusions:
- Sintering temperature is a key parameter for controlling the CeFe2 phase and microstructure to tailor magnetic properties.
- Optimizing sintering conditions, particularly around 1080 °C, can maximize coercivity while maintaining high remanence.
- Microstructural control, including grain boundary phase continuity and defect reduction, is essential for high-performance magnets.
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