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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
Magnetic X-ray absorption fine structure for Ni-Mn alloys
T Miyanaga1, T Okazaki, R Murako
1Faculty of Science and Technology, Hirosaki University, Hirosaki Aomori, Japan. takaf@cc.hirosaki-u.ac.jp
Journal of Synchrotron Radiation
|February 28, 2003
Summary
Magnetic X-ray absorption fine-structure (XAFS) studies reveal distinct local magnetic structures in Ni-Mn alloys. Mn K-edge magnetic X-ray absorption near-edge structure (XANES) intensity correlates with magnetization, unlike Ni K-edge.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Magnetism
Background:
- Nickel-Manganese (Ni-Mn) alloys exhibit complex magnetic properties.
- Understanding the local magnetic structure is crucial for alloy performance.
Purpose of the Study:
- To investigate the local magnetic structure of Ni-Mn alloys using magnetic X-ray absorption fine-structure (XAFS).
- To differentiate the magnetic behavior of Mn and Ni atoms within the alloy.
- To explore the influence of atomic ordering on magnetic properties.
Main Methods:
- Measurement of magnetic X-ray absorption near-edge structure (XANES) and X-ray magnetic circular dichroism (XMCD) at Mn and Ni K-edges.
- Analysis of magnetic extended X-ray absorption fine-structure (EXAFS) spectra.
- Semi-relativistic theoretical calculations.
Main Results:
- Local magnetic structures around Mn and Ni atoms are significantly different.
- Mn K-edge magnetic XANES peak intensity depends on sample magnetization, unlike the Ni K-edge.
- Heat treatment (atomic ordering) leads to enhanced peaks in Mn K-edge magnetic EXAFS, indicating Mn substitution in Ni shells.
Conclusions:
- The magnetic behavior of Mn and Ni atoms in Ni-Mn alloys is distinct.
- Atomic ordering induced by heat treatment alters the local magnetic environment.
- Theoretical calculations support the observed magnetic EXAFS phenomena.
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