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Updated: May 29, 2025
08:55
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
8.5K
Structural refinement and magnetic tuning in cobalt-substituted SrFe12O19 hexaferrite.
Moatoshi1, C Borgohain2, S D Kaushik3
1Department of Physics, National Institute of Technology Nagaland, Chumukedima 797103, Nagaland, India.
The Journal of Chemical Physics
|February 4, 2025
Summary
Cobalt substitution in strontium hexaferrite (SrCoM) enhances coercivity while decreasing saturation magnetization. These modified magnetic materials show promise for various applications.
Area of Science:
- Materials Science
- Solid State Chemistry
- Magnetism
Background:
- Strontium hexaferrite (SrFe12O19, SrM) is a key magnetic material.
- Transition metal substitution is a common strategy to tune magnetic properties.
Purpose of the Study:
- To synthesize and characterize cobalt-substituted strontium hexaferrite (SrFe12-xCoxO19, SrCoM).
- To investigate the impact of cobalt substitution on crystal structure and magnetic properties.
Main Methods:
- Chemical co-precipitation for synthesis.
- X-ray diffraction (XRD) and neutron powder diffraction for structural analysis.
- Rietveld refinement for detailed structural evaluation.
Main Results:
- Hexaferrite phase confirmed with minor hematite and halite impurities.
- Cobalt substitution significantly alters crystal structure and magnetic parameters.
- Increased coercivity, decreased saturation magnetization and retentivity observed with cobalt substitution.
- Ferrimagnetic ordering confirmed at ambient temperature.
Conclusions:
- Cobalt substitution effectively modifies strontium hexaferrite properties.
- SrCoM materials exhibit potential for diverse magnetic applications.
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