Articles de revues : « Crystallization Kinetics - Glasses »

1

Köster, Uwe. « Crystallization Kinetics in Metallic Glasses ». Key Engineering Materials 13-15 (janvier 1987) : 281–92. http://dx.doi.org/10.4028/www.scientific.net/kem.13-15.281.

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Suñol, Joan Josep, et J. Bonastre. « Crystallization kinetics of metallic glasses ». Journal of Thermal Analysis and Calorimetry 102, n^o 2 (28 juillet 2010) : 447–50. http://dx.doi.org/10.1007/s10973-010-0955-x.

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Paramesh, Gadige, et K. B. R. Varma. « Glass Anatase Nanocrystal Composites and their Crystallization Kinetics ». Advanced Materials Research 622-623 (décembre 2012) : 950–54. http://dx.doi.org/10.4028/www.scientific.net/amr.622-623.950.

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Nanocrystallization of anatase phase was established in BaO-TiO2-B2O3 glass system. Crystallization kinetics of anatase phase in these glasses were investigated using non-isothermal differential scanning calorimetry (DSC) at three different heating rates (10, 20 & 30 K/min). Scanning Electron Microscopy (SEM) carried out on heat treated (at 920 K) glasses confirmed bulk nucleation and three-dimensional growth. Johnson-Mehl-Avarami model could not be applied for this system suggesting considerable overlap of the nucleation and growth involving complex transformation process. However, modified Kissinger and Ozawa models were used to calculate the effective activation energy associated with anatase crystallization. The kinetic exponent n was found to be temperature dependent indicating the change in the crystallization mechanism. This was attributed to the high entropy fusion of anatase phase, fast crystallization rate and nano dimension of the anatase phase.

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Khan, Shamshad A., Imtayaz H. Khan, M. Shaheer Akhtar, Ismail Ekmekci, Tae-Geum Kim, Mohamed Hashem, Najm M. Alfrisany, Hassan Fouad et Archana Srivastava. « Structural, Crystallization Kinetics and Physical Properties of Se₈₅Te_15−xAg_x Chalcogenide Glasses ». Science of Advanced Materials 15, n^o 3 (1 mars 2023) : 434–40. http://dx.doi.org/10.1166/sam.2023.4411.

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In this study, Se85Te15−xAgx (x = 3, 6, 9 and 12) chalcogenide glasses were examined for their structure, crystallization kinetics, and physical characteristics. The kinetics of crystallization in these glasses were studied using various methods. By using the melt quenching process, Se85Te15−xAgx bulk alloys were created. The amorphous nature of the alloys was confirmed using High Resolution X-Ray Diffraction (HRXRD). The crystallization kinetics of the Se85Te15−xAgx glasses were studied using non-isothermal differential scanning calorimetry (DSC) measurements at heating speeds of 5, 10, 15, 20 and 25 K/min. The different characteristic temperatures, including the glass transition (Tg) and on-set crystallization (Tc) temperatures, have been determined from a variety of DSC thermograms. Using the Kissinger and Moynihan techniques, the activation energies of the glass transition (ΔEt) were computed.

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Wondraczek, Lothar, Joachim Deubener, Scott T. Misture et Regina Knitter. « Crystallization Kinetics of Lithium Orthosilicate Glasses ». Journal of the American Ceramic Society 89, n^o 4 (avril 2006) : 1342–46. http://dx.doi.org/10.1111/j.1551-2916.2005.00861.x.

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Kolb-Telieps, Angelika. « Crystallization Kinetics of Zr-Metal-Glasses* ». Zeitschrift für Physikalische Chemie 157, Part_1 (janvier 1988) : 389–94. http://dx.doi.org/10.1524/zpch.1988.157.part_1.389.

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Prnová, Anna, Alfonz Plško, Jana Valúchová, Peter Švančárek, Róbert Klement, Monika Michálková et Dušan Galusek. « Crystallization kinetics of yttrium aluminate glasses ». Journal of Thermal Analysis and Calorimetry 133, n^o 1 (3 janvier 2018) : 227–36. http://dx.doi.org/10.1007/s10973-017-6948-2.

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Abdel-Rahim, M. A. « Crystallization kinetics of selenium-tellerium glasses ». Journal of Materials Science 27, n^o 7 (1992) : 1757–61. http://dx.doi.org/10.1007/bf01107200.

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Málek, J., L. Tichý et J. Klikorka. « Crystallization kinetics of GexS1−x glasses ». Journal of Thermal Analysis 33, n^o 3 (septembre 1988) : 667–72. http://dx.doi.org/10.1007/bf02138571.

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Plško, Alfonz, Marek Liška et Jana Pagáčová. « Crystallization kinetics of Al2O3–Yb2O3 glasses ». Journal of Thermal Analysis and Calorimetry 108, n^o 2 (27 octobre 2011) : 505–9. http://dx.doi.org/10.1007/s10973-011-1967-x.

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Fang, Yong Zheng, Jia Yue Xu, Zhang Yong Wang et Hui Chun Qian. « Surface and Bulk Crystallization Kinetics of Er³⁺ Doped Mixed Alkali Phosphate Glasses ». Advanced Materials Research 146-147 (octobre 2010) : 1142–46. http://dx.doi.org/10.4028/www.scientific.net/amr.146-147.1142.

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DSC measurements have been carried out for the as-quenched xNa2O- (15-x)Li2O-4B2O3-11Al2O3-5BaO-65P2O5 (x=0,3.75,7.5,11.25 and 15 mol%) glasses with different particle size. Two crystallization peaks appear on the DSC curves for sample sized 90-110μm. The presence of two crystallization peaks is due to different crystallization mechanisms, surface and bulk (internal) crystallization. The X-ray diffraction measurements are also employed to investigate the crystallization of glasses. The results show that bulk crystallization is difficult to occur in the studied phosphate glasses. The effect of mixed alkali on glass thermal stability is also studied in this paper. The surface and bulk crystallization active energies are calculated according to Kissinger equation.

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Sazali, Ezza Syuhada, M. Rahim Sahar, Nur Amanina Mat Jan, Khaidzir Hamzah et Ramli Arifin. « Study of Crystallization Kinetics of TeO₂-Na₂O-MgO Glass Using Ozawa Method : Influence of Europium ». Advanced Materials Research 501 (avril 2012) : 116–20. http://dx.doi.org/10.4028/www.scientific.net/amr.501.116.

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. The study of the crystallization kinetics of rare-earth doped glass stimulated much interest especially for crystallization process. In this work transparent Eu2O3 doped glasses with composition TeO2 - Na2O – MgO were prepared using conventional melt-quenching technique. The amorphous nature of glass was confirmed using X-ray diffraction method. The influence of Eu3+ content on the crystallization kinetics of the glass such as activation energy (Ea) was thoroughly evaluated under non-isothermal conditions using DTA. The crystallization kinetic at different heating rate from 5 °C min-1 to 25 °C min-1 at different crystallization temperature (Tp) were examined and verified using Ozawa method. The result showed that the activation energy (Ea) was decreased with the increasing of the dopant concentration from 319.8 eV to 93.5 eV.

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Школьников, Е. В. « Kinetics of isothermal bulk crystallization of AsSe1,5Bix glasses (x = 0,01, 0,05) ». Известия СПбЛТА, n^o 238 (11 mars 2022) : 170–84. http://dx.doi.org/10.21266/2079-4304.2022.238.170-184.

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При легировании стекла As2Se3 оловом, свинцом или висмутом возможна изотермическая объемная кристаллизация полученных стекол в оптимальных условиях. Влияние концентрации виcмута на характер и кинетические параметры кристаллизации стекол изучено недостаточно. Проведен сравнительный анализ кинетики изотермической объемной кристаллизации стекол As2Se3 и AsSe1,5Bix (х = 0,01 и 0,05). Стекла синтезировали методом вакуумной плавки из особо чистых элементных веществ с общей массой 7 г в интервале 700−900 °С с последующей закалкой кварцевых ампул с расплавами в воздухе от 700 °С. Методами измерения плотности, микротвердости, температурной зависимости электропроводности, рентгенофазового анализа закаленных образцов исследована кинетика превращений при объемной изотермической кристаллизации стекол AsSe1,5Bi0,01 и AsSe1,5Bi0,05 в интервале температур 210−260 С. Анализ кинетики валовой кристаллизации стекол выполнен по данным измерения плотности с использованием обобщенного уравнения Колмогорова–Аврами. Добавка 2 ат.% Bi к стеклу As2Se3 ускоряла кристаллизацию основной фазы As2Se3, уменьшая, по сравнению с кристаллизацией чистого стекла As2Se3, примерно в 4 раза скрытый период начала выделения фазы As2Se3 и в 13 раз кинетический период полупревращения. Влияние добавок 0,4 и 2 ат.% Bi на изотермическую кристаллизацию стекла As2Se3 проявляется, в основном, в снижении термодинамического барьера и энергии активации объемного гетерогенного зарождения пластинчатых кристаллов фазы As2Se3 на нанокристаллах первичной фазы Bi2Se3. Реконструктивная кристаллизация основной фазы As2Se3 в стекле AsSe1,5Bi0,05 связана с непрерывным изменением химического состава остаточной стеклофазы и характеризуется интервалом уменьшающихся значений эффективной энергии активации (142 → 114 ± 5 кДж/ моль). When As2Se3 glass is doped with tin, lead, or bismuth, isothermal bulk crystallization of the resulting glasses under optimal conditions is possible. The influence of bismuth concentration on the character and kinetic parameters of glasses crystallization has not been studied sufficiently. The purpose of this work is the comparative analysis of the kinetics of isothermal volumetric crystallization of As2Se3 and AsSe1,5Bix glasses (x = 0,01 and 0,05). Glasses were synthesized by vacuum melting method from especially pure elemental substances with total mass of 7 g in the interval 700–900 С with the subsequent quenching of quartz ampoules with melts in air from 700 °С. The kinetics of transformations during bulk isothermal crystallization of AsSe1,5Bi0,01 and AsSe1,5Bi0,05 glasses in the temperature range 210–260 °С wаs studied by methods of density, microhardness, temperature dependence of electric conductivity, X-ray phase analysis of quenched samples. Analysis of the kinetics of bulk crystallization of the glasses was performed according to density measurements using the generalized Kolmogorov–Avrami equation. The addition of 2 at.% Bi to As2Se3 glass accelerated the crystallization of the main As2Se3 phase, reducing the latent period of the onset of As2Se3 phase separation by about 4 times and the kinetic period of half-transition by 13 times in comparison with the crystallization of pure As2Se3 glass. The effect of 0,4 and 2 at.% Bi additions on the isothermal crystallization of As2Se3 glass manifests itself mainly in decreasing the thermodynamic barrier and activation energy of bulk heterogeneous nucleation of lamellar As2Se3 phase crystals on primary Bi2Se3 phase nanocrystals. The reconstructive crystallization of the main phase of As2Se3 in AsSe1.5Bi0.05 glass is associated with a continuous change in the chemical composition of the residual glass phase and is characterized by an interval of decreasing values of the effective activation energy (142 → 114 ± 5 kJ/ mol).

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Е.В., Школьников,. « Kinetics of isothermal volumetric crystallization of indium doped As2Se3 glass ». Известия СПбЛТА, n^o 240 (11 décembre 2022) : 277–93. http://dx.doi.org/10.21266/2079-4304.2022.240.277-293.

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При легировании стекла As2Se3 оловом, свинцом, висмутом или индием возможна изотермическая объемная кристаллизация полученных стекол в оптимальных условиях. Влияние добавок индия на характер и кинетические параметры кристаллизации стекла As2Se3 изучено недостаточно. Цель работы − сравнительный анализ кинетики изотермической объемной кристаллизации стекол As2Se3 и AsSe1,5In0,01 (0,4 ат.% In). Стекла синтезировали методом вакуумной плавки из особо чистых элементных веществ с общей массой 7 г в интервале 700−900 С с последующей закалкой кварцевых ампул с расплавами от 900 С в потоке воздуха. Кинетику объемной изотермической кристаллизации стекол AsSe1,5In0,01 исследовали в интервале температур 200−260 С методами измерения плотности, микротвердости, температурной зависимости электропроводности и количественного рентгенофазового анализа закаленных образцов. Анализ кинетики валовой кристаллизации стекол выполнен по данным измерения эффективной плотности с использованием обобщенного уравнения Колмогорова–Аврами. Добавка 0,4 ат.% In к стеклу As2Se3 изменяла характер кристаллизации с поверхностно-объемной на равномерную по всему объему и ускоряла расстекловывание основной фазы As2Se3, уменьшая, по сравнению с чистым стеклом As2Se3, примерно в 2 раза скрытый период выделения фазы As2Se3 и в 4 раза кинетический период полупревращения при 240 С. Влияние легирования индием на изотермическую кристаллизацию стекла As2Se3 проявляется в основном в снижении термодинамического барьера и энергии активации объемного гетерогенного зарождения пластинчатых кристаллов фазы As2Se3 на нанокристаллах первичной фазы β – In2Se3. At doping of glass As2Se3 with tin, lead, bismuth or indium the isothermal volumetric crystallization of the received glasses in optimum conditions is possible. The influence of additives of indium on character and kinetic parameters of crystallization of As2Se3 glass is insufficiently studied. The aim of this work is the comparative analysis of isothermal volumetric crystallization kinetics of As2Se3 and AsSe1,5In0,01 (0,4 at. % In) glasses. Glasses were synthesized by vacuum melting method from especially pure elemental substances with total mass of 7 g in the range of 700–900 С with subsequent quenching of quartz ampoules with melts from 900 С in an air stream. Volumetric isothermal crystallization kinetics of AsSe1,5In 0,01 glasses were studied in the temperature interval of 200–260 С by methods of density measurements, microhardness, temperature dependence of conductivity, and quantitative X-ray diffraction analysis of quenched samples. Analysis of the kinetics of volumetric crystallization of glasses was performed according to effective density measurements using the generalized Kolmogorov–Avrami equation. Тhe addition of 0.4 at.% In to the As2Se3 glass changed the crystallization character from surfacevolumetric to uniform throughout the volume and accelerated the devitrification of the main As2Se3 phase, reducing about 2 times the latent period of As2Se3 phase separation and 4 times the kinetic period of half-transformation at 240 C in comparison with pure As2Se3 glass. The influence of indium doping on isothermal crystallization of As2Se3 glass is manifested mainly in reduction of thermodynamic barrier and activation energy of bulk heterogeneous nucleation of lamellar crystals of As2Se3 phase on primary phase β – In2Se3 nanocrystals.

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Rashad, M., R. Amin et M. M. Hafiz. « Crystallization kinetics of glassy Se–Te–Sn alloys ». Canadian Journal of Physics 93, n^o 8 (août 2015) : 898–904. http://dx.doi.org/10.1139/cjp-2014-0186.

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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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Bansal, Narottam P., et Mark J. Hyatt. « Crystallization kinetics of BaO–Al2O3–SiO2 glasses ». Journal of Materials Research 4, n^o 5 (octobre 1989) : 1257–65. http://dx.doi.org/10.1557/jmr.1989.1257.

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Barium aluminosilicate glasses are being investigated as matrix materials in high-temperature ceramic composites for structural applications. Kinetics of crystallization of two refractory glass compositions in the barium aluminosilicate system have been studied by differential thermal analysis (DTA), x-ray diffraction (XRD), and scanning electron microscopy (SEM). From variable heating rate DTA, the crystallization activation energies for glass compositions (wt. %) 10BaO–38Al2O3–51SiO2–1MoO3 (glass A) and 39BaO–25Al2O3–35SiO2–1MoO3 (glass B) were determined to be 553 and 558 kJ/mol, respectively. On thermal treatment, the crystalline phases in glasses A and B were identified as mullite (3Al2O3 · 2SiO2) and hexacelsian (BaO · Al2O3 · 2SiO2), respectively. Hexacelsian is a high-temperature polymorph which is metastable below 1590 °C. It undergoes structural transformation into the orthorhombic form at ∼300 °C accompanied by a large volume change which is undesirable for structural applications. A process needs to be developed where stable monoclinic celsian, rather than hexacelsian, precipitates out as the crystal phase in glass B.

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Zhilin, A. A., T. I. Chuvaeva et M. P. Shepilov. « Crystallization kinetics of sodium-niobium silicate glasses ». Glass Physics and Chemistry 26, n^o 2 (mars 2000) : 20–26. http://dx.doi.org/10.1007/bf02731939.

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Erol, M., S. Küçükbayrak, A. Ersoy-Meriçboyu et M. Lutfy Öveçoğlu. « Crystallization Kinetics of Fly Ash-Based Glasses ». Key Engineering Materials 264-268 (mai 2004) : 1895–98. http://dx.doi.org/10.4028/www.scientific.net/kem.264-268.1895.

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Deb, B., et A. Ghosh. « Crystallization kinetics in selenium molybdate molecular glasses ». EPL (Europhysics Letters) 95, n^o 2 (1 juillet 2011) : 26002. http://dx.doi.org/10.1209/0295-5075/95/26002.

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Saddeek, Yasser B., Essam R. Shaaban, K. A. Aly et I. M. Sayed. « Crystallization kinetics of Li2O–PbO–V2O5 glasses ». Physica B : Condensed Matter 404, n^o 16 (août 2009) : 2412–18. http://dx.doi.org/10.1016/j.physb.2009.04.051.

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Akhtar, D., et R. P. Mathur. « Isothermal crystallization kinetics of Ni60Nb4o-xCrx, glasses ». Journal of Materials Science 22, n^o 7 (juillet 1987) : 2509–14. http://dx.doi.org/10.1007/bf01082138.

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Fedorov, V. D., V. V. Sakharov, A. M. Provorova, P. B. Baskov, M. F. Churbanov, V. S. Shiryaev, Ma Poulain, Mi Poulain et A. Boutarfaia. « Kinetics of isothermal crystallization of fluoride glasses ». Journal of Non-Crystalline Solids 284, n^o 1-3 (mai 2001) : 79–84. http://dx.doi.org/10.1016/s0022-3093(01)00383-0.

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Çelikbilek, M., A. E. Ersundu, N. Solak et S. Aydin. « Crystallization kinetics of the tungsten–tellurite glasses ». Journal of Non-Crystalline Solids 357, n^o 1 (janvier 2011) : 88–95. http://dx.doi.org/10.1016/j.jnoncrysol.2010.09.012.

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Predeep, P., N. S. Saxena, M. P. Saksena et A. Kumar. « Crystallization kinetics of Se-Te-Cd glasses ». Physica Status Solidi (a) 156, n^o 1 (16 juillet 1996) : 23–28. http://dx.doi.org/10.1002/pssa.2211560104.

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Kaswan, Anusaiya, Vandana Kumari, Dinesh Patidar, Narendra Saxena et Kananbala Sharma. « Kinetics of crystallization of Ge30-xSe70Sbx (x=15, 20, 25) chalcogenide glasses ». Processing and Application of Ceramics 8, n^o 1 (2014) : 25–30. http://dx.doi.org/10.2298/pac1401025k.

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The kinetics of crystallization of Ge30-xSe70Sbx (x=15, 20, 25) chalcogenide glasses has been investigated using differential scanning calorimetery at different heating rates under non-isothermal conditions. The kinetic analysis of crystallization has been discussed using different theoretical approaches such as Ozawa model, Augis and Bennet model, Matusita model and Gao-Wang model. It is evident from this study that the activation energy of crystallization Ec is composition dependent. The activation energy decreases with increasing Sb content due to the increasing of rate of crystallization. The minimum value of the frequency factor Ko, which is defined as the number of attempts made by the nuclei per second to overcome the energy barrier, confirms the fact that glass is more stable. It has been found that Ge15Se70Sb15 glass is more stable compared to the other compositions.

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Huo, Yonglin, Guilu Qin, Jichuan Huo, Xingquan Zhang, Baogang Guo, Kaijun Zhang, Jun Li, Ming Kang et Yanhui Zou. « Crystallization Kinetics of Modified Basalt Glass ». Materials 13, n^o 21 (9 novembre 2020) : 5043. http://dx.doi.org/10.3390/ma13215043.

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As the raw material for the production of basalt continuous fibers in Sichuan, basalt glass (BG) and modified basalt glass (MBG) were prepared by the melt quenching method with the basalt and chemically modified basalt, respectively. The crystallization kinetics of BG and MBG were investigated by differential scanning calorimetry (DSC) according to Kissinger methods. The results revealed that it is difficult for both glasses to crystallize at a high temperature. In addition, the crystallization activation energy of MBG is much higher than that of BG, which indicates that MBG is more difficult to crystallize than BG. The crystalline phases seemed to be formed from the surface of the two glasses. The morphologies and crystal structure of the crystalline phases in the heat-treated BG and MBG were analyzed by scanning electron microscope (SEM/EDX) and XRD. It was found that only a small amount of crystalline phase can be observed in the MBG, which indicates that the crystallization ability of the MBG was greatly suppressed. Results of this initial investigation indicate that chemical modification can effectively suppress the crystallization tendency of basalt glass and improve its thermal stability, which opens up an effective way for the industrial scale and stable production of basalt fiber.

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Dey, G. K., R. T. Savalia, E. G. Baburaj et S. Banerjee. « Crystallization of ternary Zr-based glasses—Kinetics and microstructure ». Journal of Materials Research 13, n^o 2 (février 1998) : 504–17. http://dx.doi.org/10.1557/jmr.1998.0065.

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The effect of ternary addition on the thermal stability and the sequence and the kinetics of crystallization of metallic glasses Zr76Fe(24−x)Nix (x = 0, 4, 8, 12, 16, 20, 24) have been examined. It has been found that the surface crystallization occurs in the composition range 16 < x < 20, leading to the formation of an ordered Fe-rich (Fe, Ni)3Zr cubic phase, followed by the transformation of the bulk to a mixture of α−Zr and Zr2Ni. Crystallization of alloys containing 12 to 20% Fe occurs at lower temperatures by primary crystallization of Zr3(Fe, Ni), followed by decomposition of the remaining amorphous matrix by eutectic crystallization giving rise to α−Zr + Zr2Ni. At higher temperatures these alloys transform polymorphically to Zr3(Fe, Ni) in which Ni partially substitutes Fe in the Zr3Fe lattice. Copious nucleation of Zr3(Fe, Ni) phase in these alloys, leading to the formation of a nanophase structure, has been observed. This is consistent with the prediction of increasing nucleation rate for Fe-rich compositions. The crystal nucleation and growth kinetics have been examined for primary, eutectic, and polymorphic crystallization processes. The observed nucleation and growth behaviors have been rationalized by considering the role of the quenched in nuclei and the activation energies of nucleation and growth.

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Matijasevic, S. D., M. B. Tosic, S. R. Grujic, J. N. Stojanovic, V. D. Zivanovic et J. D. Nikolic. « The effect of K2O on the crystallization of niobium germanate glasses ». Science of Sintering 43, n^o 1 (2011) : 47–53. http://dx.doi.org/10.2298/sos1101047m.

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The effect of K2O content on the crystallization of niobium germanate glasses with 22.7- 24.27 wt% of GeO2 and 54.59-57.48 wt% of Nb2O5 was examined. The glasses crystallize by primary crystallization and the formed crystalline phases were K6Nb6Ge4O26, K3.8Nb5Ge3O20.4 and KNbO3. Increasing the K2O content caused a decrease in the GeO2 content of the primary phases. The effect of the K2O content on the kinetics of primary crystallization was analyzed. It was demonstrated that an increase of the K2O content decreased the activation energy of crystal growth at first of the crystallization peaks (Ec1). At second crystallization peaks the activation energies of crystal growth increased (Ec2).

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Suriñach, S., E. Illekova, G. Zhang, M. Poulain et M. D. Baró. « Optical fiber-drawing temperature of fluorogallate glasses ». Journal of Materials Research 11, n^o 10 (octobre 1996) : 2633–40. http://dx.doi.org/10.1557/jmr.1996.0331.

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The thermal properties and the crystallization behavior of fluorogallate-based glasses were analyzed. The kinetic nature of the glass transition was used to determine the temperature dependence of the viscosity and from it an estimation of the appropriate drawing temperature for an optical fiber was established. The crystallization kinetics were studied by using both isothermal and continuous heating regimes. The temperature range for nucleation was evaluated and for samples previously nucleated the activation energy of the growth process was found. The results were used to estimate the empirical nucleation and crystal growth rates from which the time-temperature-transformation curves and the temperature-heating rate-transformation diagrams were constructed. The results obtained agree with experimental data and are discussed in the light of minimizing the volume of crystals formed during fiber drawing.

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Moharram, A. H., A. A. Abu-sehly, M. Abu El-Oyoun et A. S. Soltan. « Pre-crystallization and crystallization kinetics of some Se-Te-Sb glasses ». Physica B : Condensed Matter 324, n^o 1-4 (novembre 2002) : 344–51. http://dx.doi.org/10.1016/s0921-4526(02)01421-7.

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Gibson, M. A., et G. W. Delamore. « Crystallization Kinetics of Fe–Si–B Metallic Glasses ». Canadian Metallurgical Quarterly 29, n^o 3 (juillet 1990) : 227–31. http://dx.doi.org/10.1179/cmq.1990.29.3.227.

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Cheng, Yin, Hanning Xiao, Wenming Guo et Weiming Guo. « Structure and crystallization kinetics of Bi2O3–B2O3 glasses ». Thermochimica Acta 444, n^o 2 (mai 2006) : 173–78. http://dx.doi.org/10.1016/j.tca.2006.03.016.

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Ziani, N., M. Belhadji, L. Heireche, Z. Bouchaour et M. Belbachir. « Crystallization kinetics of chalcogenide glasses doped with Sb ». Physica B : Condensed Matter 358, n^o 1-4 (avril 2005) : 132–37. http://dx.doi.org/10.1016/j.physb.2004.12.068.

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Zhang, S. N., T. J. Zhu et X. B. Zhao. « Crystallization kinetics of Si15Te85 and Si20Te80 chalcogenide glasses ». Physica B : Condensed Matter 403, n^o 19-20 (octobre 2008) : 3459–63. http://dx.doi.org/10.1016/j.physb.2008.05.008.

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Çelikbilek Ersundu, M., et A. E. Ersundu. « Structure and crystallization kinetics of lithium tellurite glasses ». Journal of Non-Crystalline Solids 453 (décembre 2016) : 150–57. http://dx.doi.org/10.1016/j.jnoncrysol.2016.10.007.

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Gomes Fernandes, Roger, Paula Squinca Valle, Douglas Faza Franco et Marcelo Nalin. « Crystallization kinetics study of silver-doped germanium glasses ». Thermochimica Acta 673 (mars 2019) : 40–52. http://dx.doi.org/10.1016/j.tca.2019.01.013.

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dos Santos, D. S., et D. R. dos Santos. « Crystallization kinetics of Fe–B–Si metallic glasses ». Journal of Non-Crystalline Solids 304, n^o 1-3 (juin 2002) : 56–63. http://dx.doi.org/10.1016/s0022-3093(02)01004-9.

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Bordas, S., M. T. Clavaguera-Mora et N. Clavaguera. « Crystallization kinetics of some Ge-Sb-Se glasses ». Thermochimica Acta 133 (octobre 1988) : 293–98. http://dx.doi.org/10.1016/0040-6031(88)87172-7.

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Sung, Yun-Mo. « Crystallization kinetics of fluoride nanocrystals in oxyfluoride glasses ». Journal of Non-Crystalline Solids 358, n^o 1 (janvier 2012) : 36–39. http://dx.doi.org/10.1016/j.jnoncrysol.2011.08.016.

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Gibson, M. A., et G. W. Delamore. « Crystallization kinetics of some iron-based metallic glasses ». Journal of Materials Science 22, n^o 12 (décembre 1987) : 4550–57. http://dx.doi.org/10.1007/bf01132062.

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Cheng, Yin, Hanning Xiao, Wenming Guo et Weiming Guo. « Structure and crystallization kinetics of PbO–B2O3 glasses ». Ceramics International 33, n^o 7 (septembre 2007) : 1341–47. http://dx.doi.org/10.1016/j.ceramint.2006.04.025.

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Zanotto, Edgar Dutra. « Surface crystallization kinetics in soda-lime-silica glasses ». Journal of Non-Crystalline Solids 129, n^o 1-3 (mars 1991) : 183–90. http://dx.doi.org/10.1016/0022-3093(91)90094-m.

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Palou, Martin, Eva Kuzielová, Martin Vitkovič et Maha Noaman. « Mechanism and kinetics of glass-ceramics formation in the LiO2-SiO2-CaO-P2O5-CaF2 system ». Open Chemistry 7, n^o 2 (1 juin 2009) : 228–33. http://dx.doi.org/10.2478/s11532-009-0002-6.

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AbstractTwo glasses based on lithium disilicate (LS2), with and without fluorapatite (FA), were synthesised in the Li2O-SiO2-CaO-P2O5-CaF2 system with P2O5: CaO: CaF2 ratios corresponding to fluorapatite. Glass-ceramics have then been prepared by thermal treatment. The mechanism and kinetics of crystallization as functions of grain size and rate of heating were investigated using thermal analysis methods. The smaller particles crystallize preferentially by surface crystallization, which is replaced by volume crystallization at larger particle sizes. Inclusion of FA in the LS2 favours crystallization through the surface mechanism. The onset limit for volume crystallization replacing the surface mechanism is at about 0.3 mm for pure LS2 glass and 0.9 mm for glass containing FA. The calculated activation energies of the glasses (299 ± 1 kJ mol-1 for pure LS2 glass and 288 ± 7 kJ mol−1 for glass containing FA according to Kissinger, or 313 ± 1 kJ mol-1 for pure LS2 glass and 303 ± 8 kJ mol-1 for glass containing FA according to Ozawa) indicate that the tendency of the glasses to crystallize is supported by the FA presence. Bioactivity of all samples has been proved in vitro by the formation of new layers of apatite-like phases after soaking in SBF.

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Rocca, J. A., M. A. Ureña et M. R. Fontana. « MASTER CURVE FOR CRYSTALLIZATION OF SB70TE30AMORPHOUS ALLOYS ». Anales AFA 34, n^o 1 (28 mars 2023) : 22–26. http://dx.doi.org/10.31527/analesafa.2023.34.1.22.

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One of the possible uses of chalcogenide glasses is their application in phase change memory devices. The operation of these non-volatile memories is based on the use of an alloy with chalcogenide elements as a sensitive material, taking advantage of the great contrast in electrical resistance between the amorphous and crystalline states. The Sb70Te30(atomic percentage) alloy stands out among the chalcogenide materials with these properties. On the other hand, the knowledge of the microscopic mechanisms of the amorphous alloys crystallization allows microstructural control to optimize properties. At this point, differential scanning calorimetry (DSC) has been widely used for the determination of the thermal stability of amorphous alloys. Previously we have started the study of the crystallization kinetics ofSb70Te30amorphous alloys. In this work, a procedure based on the so-called isokinetic hypothesis has been applied to carry out the kinetic analysis of the calorimetric data of continuous heating. In particular, the so-called master curve of the crystallization kinetics of this alloy is determined.

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Seera, Sai Mohan, et Paramesh Gadige. « Nonisothermal Crystallization-Kinetic Studies on Ag+ Ion-Exchanged Silicate Glasses : Silver Nanocrystals Growth-Kinetics in Glasses ». Journal of Non-Crystalline Solids 544 (septembre 2020) : 120166. http://dx.doi.org/10.1016/j.jnoncrysol.2020.120166.

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Jean, Jau-Ho, et Tapan K. Gupta. « Crystallization kinetics of binary borosilicate glass composite ». Journal of Materials Research 7, n^o 11 (novembre 1992) : 3103–11. http://dx.doi.org/10.1557/jmr.1992.3103.

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Kinetics of cristobalite precipitation in a binary glass composite, containing a low-softening borosilicate (BSG) and a high-softening high silica (HSG) glass, have been investigated. XRD results show that the pure glasses do not crystallize under the sintering conditions used, but when mixed in appropriate proportions the cristobalite gradually precipitates out of the initial amorphous binary glass mixture as the sintering continues at temperatures ranging from 800 to 1000 °C. Average linear thermal expansion coefficient (TCE) results show that the TCE increases significantly with increasing precipitation of cristobalite as a function of sintering time. Comparing the experimental TCE results with those theoretically calculated, it is concluded that the precipitation originates most likely in the HSG rather than in the BSG. The precipitation kinetics follow the Avrami equation, and the results show an apparent activation energy of 82 kJ/mol which is close to those for the diffusion of alkali ions in silicate glasses, suggesting mass-transport controlled kinetics. The values of the Avrami exponent are 1.7–1.8, which could be interpreted as a 3-dimension diffusional growth at zero nucleation rate. The linear growth rates of cristobalite, calculated from the precipitation curve, are in the range of 4–8 × 10−5 μm/min, and show slight temperature dependence from 800 to 1000 °C. The linear growth rates of cristobalite are also calculated theoretically using the equation derived by Turnbull et al.,2 and the data are 0–3 orders of magnitude smaller than those observed experimentally. This disparity is attributed to the catalytic effect of the OH and O in air and in the glass network, as well as the diffusion of alkali ions from BSG to HSG.

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Duan, Tianrui, Ye Shen, Seth D. Imhoff, Feng Yi, Paul M. Voyles et John H. Perepezko. « Nucleation kinetics model for primary crystallization in Al–Y–Fe metallic glass ». Journal of Chemical Physics 158, n^o 6 (14 février 2023) : 064504. http://dx.doi.org/10.1063/5.0135730.

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The high density of aluminum nanocrystals (>1021 m−3) that develop during the primary crystallization in Al-based metallic glasses indicates a high nucleation rate (∼1018 m−3 s−1). Several studies have been advanced to account for the primary crystallization behavior, but none have been developed to completely describe the reaction kinetics. Recently, structural analysis by fluctuation electron microscopy has demonstrated the presence of the Al-like medium range order (MRO) regions as a spatial heterogeneity in as-spun Al88Y7Fe5 metallic glass that is representative for the class of Al-based amorphous alloys that develop Al nanocrystals during primary crystallization. From the structural characterization, an MRO seeded nucleation configuration is established, whereby the Al nanocrystals are catalyzed by the MRO core to decrease the nucleation barrier. The MRO seeded nucleation model and the kinetic data from the delay time ( τ) measurement provide a full accounting of the evolution of the Al nanocrystal density (Nv) during the primary crystallization under isothermal annealing treatments. Moreover, the calculated values of the steady state nucleation rates ( J ss) predicted by the nucleation model agree with the experimental results. Moreover, the model satisfies constraints on the structural, thermodynamic, and kinetic parameters, such as the critical nucleus size, the interface energy, and the volume-free energy driving force that are essential for a fully self-consistent nucleation kinetics analysis. The nucleation kinetics model can be applied more broadly to materials that are characterized by the presence of spatial heterogeneities.

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Mu, Juan, et Hai Feng Zhang. « Glass Forming Ability and Crystallization Kinetics of Al-Mg-Ni-La Metallic Glasses ». Advanced Materials Research 960-961 (juin 2014) : 161–64. http://dx.doi.org/10.4028/www.scientific.net/amr.960-961.161.

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Glass forming ability and crystallization kinetics of Al-Mg-Ni-La alloys have been investigated by X-ray diffraction (XRD) and differential scanning calorimetry (DSC). The maximum thickness achievable in glasses of Al76Mg11Ni8La5and Al69Mg18Ni8La5ribbons were 200 and 120 μm, respectively. The crystallization temperature and peak temperature indicated by DSC measurements displayed dependence on the heating rate during continuous heating, and were coincident with Lanoka’s relationship. The activation energies for the crystallization reactionExwere obtained from the Kissinger’s equation. The results show the Mg addition is beneficial to the thermal stability of the amorphous phase.

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Hermann, H. U. « Crystallization Kinetics of Metallic Glasses on a Nanometer Scale ». Materials Science Forum 307 (mars 1999) : 113–18. http://dx.doi.org/10.4028/www.scientific.net/msf.307.113.

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Hermann, H. U. « Crystallization Kinetics of Metallic Glasses on a Nanometer Scale ». Journal of Metastable and Nanocrystalline Materials 1 (mars 1999) : 113–18. http://dx.doi.org/10.4028/www.scientific.net/jmnm.1.113.

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