Nonisothermal crystallisation kinetics of amorphous selenium prepared by high-energy ball milling: A comparison with the melt-quenching and thin-film techniques
Autor: | Mohamed Benghanem, A.A. Abu-Sehly, A.A. Joraid, S.N. Alamri |
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Rok vydání: | 2012 |
Předmět: |
Quenching
Materials science Analytical chemistry Activation energy Condensed Matter Physics Endothermic process Electronic Optical and Magnetic Materials Amorphous solid law.invention Differential scanning calorimetry law Materials Chemistry Ceramics and Composites Crystallization Ball mill Diffractometer |
Zdroj: | Journal of Non-Crystalline Solids. 358:1268-1273 |
ISSN: | 0022-3093 |
Popis: | Differential scanning calorimetry (DSC) studies were performed under nonisothermal conditions at various heating rates for glassy Se made by high-energy ball milling. Comparisons were made between the ball-milling technique and the melt-quenching and thin-film techniques. Well-defined endothermic and exothermic peaks were observed at the glass-transition temperature, Tg, and the onset temperature of crystallisation, Tc. The isoconversional method of Vyazovkin was used to determine the variation in the activation energy for crystallisation with temperature, Eα(T). The value of Eα(T) was dependent on the sample preparation method. The thermal stability of the Se glasses was evaluated by calculation of the temperature difference (Tc − Tg) and the S-parameter. In addition, the glass-forming ability was estimated by the criteria of reduced glass-transition temperature, Trg, and the Hruby number, HR. The structures of the Se samples that resulted from the DSC analysis were identified using an X-ray diffractometer. The glasses formed using the thin film technique were the most stable. |
Databáze: | OpenAIRE |
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