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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
Medium range order of bulk metallic glasses determined by variable resolution fluctuation electron microscopy.
1Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang 110016, China.
Micron (Oxford, England : 1993)
|March 7, 2012
Summary
Variable resolution fluctuation electron microscopy (FEM) determines medium-range order in metallic glasses and silicon nitride. Maximum image intensity variance indicates resolution matching the material
Area of Science:
- Materials Science
- Condensed Matter Physics
- Electron Microscopy
Background:
- Understanding medium-range order (MRO) is crucial for characterizing amorphous materials.
- Traditional methods for MRO determination can be limited in scope and resolution.
Purpose of the Study:
- To implement variable resolution fluctuation electron microscopy (VR-FEM) for MRO analysis.
- To determine MRO lengths in bulk metallic glasses (BMGs) and amorphous silicon nitride.
- To compare MRO characteristics between metallic and covalent amorphous materials.
Main Methods:
- Utilizing hollow-cone dark-field transmission electron microscopy for FEM experiments.
- Analyzing normalized intensity variances in FEM images to identify correlation lengths.
- Comparing MRO parameters across different amorphous material types.
Main Results:
- Successfully determined MRO lengths for Zr- and Fe-based BMGs and amorphous SiN.
- Observed that maximum intensity variances in FEM images correlate with the material's correlation length (Λ).
- Quantified differences in MRO length and magnitude between metallic and covalent amorphous materials.
Conclusions:
- VR-FEM is an effective technique for quantifying MRO in amorphous solids.
- The correlation length (Λ) is a critical parameter influencing FEM image characteristics.
- Distinct MRO behaviors exist between metallic and covalent amorphous systems.
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