Kinetics of the glass transition in As22S78 chalcogenide glass: Activation energy and fragility index

Structural and thermal measurements have been performed in glassy Se78Te18M4 (M = Sb and Ge) alloys to study the effect of Sb and Ge additives on the kinetics of glass transition and crystallization. Kinetic parameters of glass transition and crystallization such as the activation energy of glass transition (Eg), the activation energy of crystallization (Ec) have been determined using different non-isothermal methods. It was found that Ge was more suitable dopant for phase change memory (PCM) devices due to its low activation energies as compared to Sb dopant.

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Crystallization kinetics of glassy Se–Te–Sn alloys

Canadian Journal of Physics ◽

10.1139/cjp-2014-0186 ◽

2015 ◽

Vol 93 (8) ◽

pp. 898-904 ◽

Cited By ~ 3

Author(s):

M. Rashad ◽

R. Amin ◽

M.M. Hafiz

Keyword(s):

Activation Energy ◽

Glass Transition ◽

Present Article ◽

Crystallization Kinetics ◽

Isothermal Crystallization ◽

Composition Dependence ◽

Thermal Analyses ◽

Heating Rates ◽

Glass Transition Temperatures ◽

Kinetics Of

The present article deals with the differential thermal analyses (DTA) study of Se–Te glasses containing Sn. DTA runs are taken at six different heating rates (5, 10, 15, 18, 20, and 22 K min−1). The crystallization data are examined in terms of modified Kissinger, Mahadevan method, and Augis and Bennett approximation for the non-isothermal crystallization. Results of DTA under non-isothermal conditions on the glasses of the Se80Te20--xSnx (x = 3 and 9) are reported and discussed at different heating rates. The glass transition temperatures (Tg), the onset crystallization temperatures (Tc), and the peak temperature of crystallization (Tp) were found to be dependent on the compositions and the heating rates. From the dependence on heating rates of (Tg) and (Tp) the activation energy for glass transition (Eg) and the activation energy for crystallization (Ec) are calculated and their composition dependence discussed.

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Glass transition behavior and crystallization kinetics of Cu0.3(SSe20)0.7 chalcogenide glass

Thermochimica Acta ◽

10.1016/j.tca.2005.05.008 ◽

2005 ◽

Vol 435 (2) ◽

pp. 129-134 ◽

Cited By ~ 6

Author(s):

A.A. Soliman

Keyword(s):

Glass Transition ◽

Chalcogenide Glass ◽

Crystallization Kinetics ◽

Transition Behavior ◽

Kinetics Of

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Theoretical and Experimental Parameters of the Structure and Crystallization Kinetics of Melt-Quenched As30Te64Ga6 Glassy Alloy

10.21203/rs.3.rs-205540/v1 ◽

2021 ◽

Author(s):

Abdelazim M. Mebed ◽

Meshal Alzaid ◽

R.M. Hassan ◽

Alaa Abd-Elnaiem

Keyword(s):

Activation Energy ◽

Glass Transition ◽

Kinetic Parameters ◽

Crystallization Kinetics ◽

Glassy Alloy ◽

Characteristic Temperature ◽

Nominal Composition ◽

Scanning Calorimetry ◽

X Ray ◽

Kinetics Of

Abstract The present framework reports the structural, fundamental parameters, and crystallization kinetics of the melt-quenched As30Te64Ga6 chalcogenide glass. The energy dispersive X-ray analysis of the As30Te64Ga6 glassy system reveals that the constituent element ratio of the investigated bulk sample agrees with the nominal composition. Also, X-ray diffraction (XRD) and Differential Scanning Calorimetry (DSC) were used to characterize crystallization kinetics, and structural properties; respectively. Four characteristic temperatures related to various phenomena are observed in the investigated DSC traces. The first one is Tg that corresponds to the glass transition temperature. The second one is TC1, and TC2 that corresponds to the onset of the double crystallization temperatures. The third one TP1, and TP2 identifies the double peak crystallization temperatures. The last characteristic temperature Tm is the melting point. The XRD analysis indicates the amorphous structure of the as-prepared glassy alloy, while the annealed samples are polycrystalline. The crystallization kinetics of the As30Te64Ga6 bulk are studied under non-isothermal conditions. In addition, the values of various kinetic parameters such as the glass transition activation energy, weight stability standard, and Avrami support were determined. The activation energy of the crystallization process for As30Te64Ga6 glass alloy was calculated using classical methods. The results indicated that the rate of crystallization is related to thermal stability and the ability to form glass. Kinetic parameters have been estimated with some conventional methods and found to be dependent on heating rates (β).

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STUDY OF GLASS TRANSITION KINETICS FOR Co66Si12B16Fe4Mo2 METALLIC GLASS

International Journal of Modern Physics Conference Series ◽

10.1142/s2010194513010295 ◽

2013 ◽

Vol 22 ◽

pp. 321-326 ◽

Cited By ~ 2

Author(s):

ASHMI T. PATEL ◽

ARUN PRATAP

Keyword(s):

Glass Transition ◽

Metallic Glass ◽

Glass Forming Ability ◽

Fragility Index ◽

Heating Rates ◽

Scanning Calorimetry ◽

Glass Transition Kinetics ◽

Glass Forming ◽

The Given ◽

Kinetics Of

Metallic glasses have received considerable attention in comparison to normal metallic materials due to their superior physical, mechanical, electrical and magnetic properties. Understanding the glass transition kinetics of metallic alloys is of great importance in order to know its thermal stability. In the present paper, kinetics of glass transition of metallic glass Co66Si12B16Fe4Mo2 is studied using thermal analysis technique, i.e. differential scanning calorimetry (DSC), by non-isothermal heating of the sample at four different heating rates. The activation energy (E) of the glass transition region is determined by two most frequently used methods, namely, Moynihan’s method and Kissinger’s equation. The fragility index, m is also calculated using Tg, which is a measure of glass forming ability of the given system. The results show that the fragility index ‘m’ of the given system falls below 16. This clearly indicates that the given system is strong liquid with excellent glass forming ability (GFA).

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Effect of ionizing radiation on the kinetics of hydrogenation on the Ni-MgO mixed catalyst

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19821780 ◽

1982 ◽

Vol 47 (7) ◽

pp. 1780-1786 ◽

Cited By ~ 2

Author(s):

Rostislav Kudláček ◽

Jan Lokoč

Keyword(s):

Experimental Data ◽

Activation Energy ◽

Liquid Phase ◽

Ionizing Radiation ◽

Oxide Catalyst ◽

Absorbed Dose ◽

Hydrogenation Rate ◽

Solution Composition ◽

Mixed Catalyst ◽

Kinetics Of

The effect of gamma pre-irradiation of the mixed nickel-magnesium oxide catalyst on the kinetics of hydrogenation of maleic acid in the liquid phase has been studied. The changes of the hydrogenation rate are compared with the changes of the adsorbed amount of the acid and with the changes of the solution composition, activation energy, and absorbed dose of the ionizing radiation. From this comparison and from the interpretation of the experimental data it can be deduced that two types of centers can be distinguished on the surface of the catalyst under study, namely the sorption centres for the acid and hydrogen and the reaction centres.

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