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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
Crystallization of bismuth borate glasses
1Department of Applied Physics, Guru Nanak Dev University, Amritsar 143005, Punjab, India.
Summary
Bismuth borate glasses were prepared and heat-treated to study crystallization. The study identified stable crystalline phases, Bi(3)B(5)O(12) and Bi(4)B(2)O(9), and a metastable phase, BiBO(3), which decomposes upon further heating.
Area of Science:
- Materials Science
- Solid State Chemistry
- Glass Science
Background:
- Bismuth borate glasses are of interest due to their unique properties.
- Understanding their crystallization behavior is crucial for material applications.
Purpose of the Study:
- To investigate the crystallization of bismuth borate glasses with varying Bi(2)O(3) concentrations.
- To identify the crystalline phases formed during devitrification and their stability.
Main Methods:
- Preparation of bismuth borate glasses using melt quenching.
- Devitrification via heat treatment above glass transition temperatures.
- Characterization of crystalline phases using FTIR absorption spectroscopy and Differential Scanning Calorimetry (DSC).
Main Results:
- All glasses exhibited a strong tendency to crystallize upon annealing, increasing with Bi(2)O(3) content.
- The stable crystalline phases identified were Bi(3)B(5)O(12) and Bi(4)B(2)O(9).
- A metastable phase, BiBO(3), was observed in glass with 50 mol% Bi(2)O(3), decomposing into stable phases with prolonged heat treatment.
Conclusions:
- The initial glass composition significantly dictates the crystalline phases formed.
- Bi(3)B(5)O(12) and Bi(4)B(2)O(9) are the most stable crystalline phases in these systems.
- The metastable BiBO(3) phase is transient and transforms into more stable phases under specific thermal conditions.
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