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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
Pressure-induced amorphization in mayenite (12CaO·7Al2O3)
Xinxin Zhang1, Yanchao Wang, Hui Wang
1State Key Laboratory of Superhard Materials, Jilin University, Changchun 130012, People's Republic of China.
The Journal of Chemical Physics
|September 15, 2011
Summary
High pressure transforms nanoporous mayenite into an amorphous state around 13 GPa. This pressure-induced amorphization is reversible and linked to cage deformations within the material.
Area of Science:
- Materials Science
- Solid State Chemistry
- High-Pressure Physics
Background:
- Nanoporous mayenite (12CaO·7Al(2)O(3)) exhibits unique structural properties.
- Understanding its behavior under extreme conditions is crucial for potential applications.
Purpose of the Study:
- To investigate the high-pressure structural response of nanoporous mayenite.
- To elucidate the mechanism of pressure-induced amorphization.
Main Methods:
- In situ high-pressure X-ray diffraction experiments up to ~13 GPa.
- Ab initio theoretical calculations.
Main Results:
- Identified pressure-induced amorphization of nanoporous mayenite at approximately 13 GPa.
- The amorphous phase is stable upon decompression to ambient conditions.
- Anisotropic deformation of empty cages, influenced by oxygen ion distribution, drives amorphization.
Conclusions:
- Nanoporous mayenite undergoes reversible amorphization under high pressure.
- The local structural geometry of empty cages dictates the deformation pathways leading to the amorphous state.
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