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Updated: Jan 23, 2026

Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Study of Crystallization and Coalescence of Nanocrystals in Amorphous Glass at High Temperature
Ting Wang1, Wei Lu1,2, Xuhui Xu1,3
1Department of Applied Physics , The Hong Kong Polytechnic University , Hong Kong , China.
Abstract:
Amorphous fluoride glass is used as the reaction chamber (i.e., solid cell) to grow Ba2LaF7 (BLF) nanocrystals at elevation temperatures (i.e., 300-500 °C) so that in situ real-time crystallization and coalescence of BLF nanocrystals can be observed. Due to the inherent advantages of the liquid-like solid medium, high temporal and spatial resolution transmission electron microscopy images can be obtained. Hence, we reveal that the twinned and quadruplet BLF nanocrystals are formed at low temperature (≤430 °C) and the unification of two nanocrystals via the two pathways (i.e., migration with and without rotation) to a single defect-free BLF nanocrystal is favored at high temperature (≥470 °C).
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