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Investigation of Crystallization Kinetics in Glassy Se and Binary Se98M2 (M=Ag, Cd, Zn) Alloys Using DSC Technique in Non-Isothermal Mode  [PDF]
Chandrabhan Dohare, Neeraj Mehta
Journal of Crystallization Process and Technology (JCPT) , 2012, DOI: 10.4236/jcpt.2012.24025
Abstract: The crystallization kinetics of glassy Se and binary Se98M2 (M=Ag, Cd, Zn) alloys have been studied at different heating rates (5, 10, 15, 20 Kmin-1) using Differential Scanning Calorimetric (DSC) technique. The crystallization temperature (Tc) is determined from exothermic peak obtained in DSC scans of present samples. The variation in peak crystallization temperature (Tc) with the heating rate (β) has been used to investigate the growth kinetics using Kissinger, Augis-Bennet and Matusita-Sakka models. The activation energy of crystallization (Ec) has been found to increase with Ag additive and to decrease with Zn and Cd additive. The value of various kinetic parameters such as rate constant (Kp), Avrami index (n), thermal stability (S) and Hruby number (Hr) have been calculated under non-isothermal mode. The maximum change in different kinetic parameters has been found after the incorporation of Ag additive.
Application of Single Scan Differential Scanning Calorimetry Technique for Determination of Kinetic Parameters of Crystallisation in Se-Sb-Ag  [PDF]
Nidhi Yaduvanshi, Deepak Kumar, Nikhil Rastogi, Ashok Kumar
Journal of Crystallization Process and Technology (JCPT) , 2019, DOI: 10.4236/jcpt.2019.91001
A single scan has been performed in Differential Scanning Calorimetry (DSC) at a heating rate of 15oC/min under non-isothermal conditions to investigate the crystallization kinetics of glassy Se90Sb10-xAgx alloys (where x = 2, 4, 6, 8). For this purpose, Handerson’s theory based on non-isothermal method for thermal analysis of single-scan DSC data has been used. The activation energy of crystallization and order parameter has been determined and composition dependence of these parameters has been discussed.
HY Zhao,H Wang,QJ Liu,
H. Y. Zhao
,H. Wang,Q.J. Liu,J.D. Kan and Z.Q. Liu

金属学报(英文版) , 2002,
Abstract: Shock wave and annealing crystallization of amorphous alloys FeSiB, FeMoSiB and FeCuNbSiB were studied by isothermal and non-isothermal DSC technique. It was found that the shock wave crystallization is very perfect, the fraction crystallized is very close to 100%, though the period of crystallization is very short, only about 10-4-10-6s. Their produced phases differ from the parent phase in structure and composition. The high velocity of the transformation is very difficult to explain by the diffusion theory of solid state phase transition.

金属学报 , 1984,
Abstract: The thermal stability and the crystallization of PdTa_1Si_(16.5) alloy of different glassy states have been studied by means of the differential scanning calorimeter (DSC). The behaviour of glass transformation and crystallization as well as the thermal stability in both states as-quenched and as-annealed are varied with the non-crystalline alloys of different glassy state owing to change of the quenching rates.
Kinetics Study of (Se80Te20)100–xCdx Glassy Alloy by Differential Thermal Analysis Using Non-Isothermal Technique  [PDF]
Mainika,N. Thakur
Journal of Nano- and Electronic Physics , 2011,
Abstract: The kinetics of crystallization in (Se80Te20)100 – xCdx (x = 0, 2, 4 and 6) alloys at different heating rates have been studied by Differential Thermal Analysis in non-isothermal condition. A comparison of various quantitative methods to assess the level of stability of the glassy material in the above mentioned system is presented. All these methods are based on the characteristics temperature obtained by heating of the samples, such as glass transition temperature (Tg), temperature of crystallization (Tc), and the melting temperature (Tm). From the dependence of glass transition temperature on heating rate, the activation energy (Eg) has been calculated on the basis of the Kissinger and Moynihan models.
Iso-conversional analysis of glass transition and crystallization in as-synthesis high yield of glassy Se98Cd2 nanorods
C. Dohare,N. Mehta
Applied Nanoscience , 2013, DOI: 10.1007/s13204-012-0143-3
Abstract: In the present work, we have prepared high yield of glassy Se98Cd2 nanorods using melt–quench technique. The morphology and micro-structural analysis of as-prepared nanorods are characterized by SEM, XRD and EDX techniques. The glass transition and crystallization kinetics of glassy Se98Cd2 nanorods are studied at different heating rates (5, 10, 15, 20 K/min) using differential scanning calorimetric (DSC) technique. Four iso-conversional methods [Kissinger–Akahira–Sunose (KAS), Flynn–Wall–Ozawa (FWO), Tang and Straink] were used to determine the various kinetic parameters (crystallization temperature T αc, transition temperature T αg, activation energy of crystallization E αc, activation energy of glass transition E αg, order parameter n) of glass transition and crystallization process in non-isothermal mode. The monotonous decrease in activation energy E α with the crystallization fraction α confirm the complex kinetic mechanism of the glassy Se98Cd2 nanorods.

WANG Dapeng,BAO Xiaoqian,ZHANG Maocai,ZHU Jie,

金属学报 , 2009,
Abstract: Crystallization processes and non–isothermal crystallization kinetics of Nd6Fe72B22 and Nd6Fe68Ti4B17C5 amorphous thick ribbons rapidly quenched at a roller running rate of 12 m/s were investigated by means of DSC, XRD, Kempen model and Kissinger equation, respectively. Two thick ribbons show different crystallization processes and kinetic mechanisms. The crystallization processes of Nd6Fe72B22 and Nd6Fe68Ti4B17C5 alloys can be discribed as: amorphous phase (AP)→ Nd2Fe23B3→Nd2Fe14B+ α--Fe +Fe3B→Nd2Fe14B+α--Fe+Fe3B+NdFe4B4, and AP→Nd2(Fe, Ti)14(B, C)+α--Fe + Fe3B, respectively. Different from polymorphic crystallization controlled by interface for Nd6Fe72B22 alloy, the crystallization of Nd6Fe68Ti4B17C5 is eutectoidic and the nucleus growth is controlled by diffusion.
The glass transition and crystallization kinetic studies on BaNaB9O15 glasses  [PDF]
Rahul Vaish,K. B. R. Varma
Physics , 2009, DOI: 10.1088/0022-3727/42/1/015409
Abstract: Transparent glasses of BaNaB9O15 (BNBO) were fabricated via the conventional melt-quenching technique. The amorphous and the glassy nature of the as-quenched samples were respectively, confirmed by X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC). The glass transition and crystallization parameters were evaluated under non-isothermal conditions using DSC. The correlation between the heating rate dependent glass transition and the crystallization temperatures was discussed and deduced the Kauzmann temperature for BNBO glass-plates and powdered samples. The values of the Kauzmann temperature for the plates and powdered samples were 776 K and 768 K, respectively. Approximation-free method was used to evaluate the crystallization kinetic parameters for the BNBO glass samples. The effect of the sample thickness on the crystallization kinetics of BNBO glasses was also investigated.
Thermal Properties of Se100–xZnx Glassy System  [PDF]
Mohd Nasir, Mohd Abdul Majeed Khan, Mushahid Husain, Mohammad Zulfequar
Materials Sciences and Applications (MSA) , 2011, DOI: 10.4236/msa.2011.25038
Abstract: The crystallization process in Se100–xZnx glassy system is investigated using differential scanning calorimeters (DSC). The samples are prepared by conventional melt-quenching technique in the composition range 2 ≤ x ≤ 20 (at%). Non-isothermal measurements are carried out for different heating rates .The value of the glass transition temperature Tg the crystallization temperature Tc and the crystallization peak temperature Tp, are found to be depending upon both heating rate as well as the composition from thermal analytical data. The investigation of crystallization kinetics indicates a single stage crystallization process. The glass transition energy Eg and the crystallization activation energy Ec are also evaluated from thermal analytical data. The analyzer has been used the most reliable non-isothermal kinetic methods. The value of kinetics parameters Eg, Ec and ‘n’ are calculated using non-isothermal kinetics methods. The analysis shows that the incorporation of Zinc content has a strong influence on the crystallization mechanism for the Se100–xZnx glassy system.
Thermal Characterization of Se80-xTe20Inx Glasses Using Iso-Conversional Methods  [PDF]
Renu Shukla, Pragya Agarwal, Ashok Kumar
Journal of Crystallization Process and Technology (JCPT) , 2012, DOI: 10.4236/jcpt.2012.22009
Abstract: Alloys of Se80-xTe20Inx glassy system are obtained by quenching technique and crystallization kinetics has been studied using Differential Scanning Calorimetric [DSC] technique. Well defined endothermic and exothermic peaks are ob- served at glass transition temperature (Tg) and crystallization temperature (Tc). From DSC scans, Tc is obtained at dif- ferent heating rates (5, 10, 15, 20, 25 K/min). It is observed that Tc increases with increasing heating rate for a particular glassy alloy. Activation energy of crystallization (Ec) has been calculated by different Non-isothermal Iso-conversional methods, i.e., Kissinger-Akahira-Sunose [KAS], Friedman, Flynn-wall-Ozawa [FWO], Friedman-Ozawa [FO] and Sta-rink methods. It is observed that Ec is dependent on extent of crystallization (α). Activation energy is also found to vary with atomic percentage of In in ternary Se80-xTe20Inx glassy system. The compositional dependence of Ec shows a re-versal in the trend at x = 15 in Se80-xTe20Inx, which is explained in terms of mechanically stabilized structure at this composition.
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