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, and no radioactivity [1–3]. It is usually prepared by melt crystallization, controlling different temperatures of the mother phase glass with the different chemical composition [4–7]. JANG et al [8] melted... and the main crystalline phase became wollastonite. This result indicated that rising temperature promoted reactive crystallization. The effect of different heat preservation times at the sintering......
is not valid to the isochronal crystallization kinetics is discussed. Key words: amorphous alloys; phase transition; thermal analysis; crystallization kinetics; JMA model  ... a large supercooled liquid region ?Tx (defined as the temperature region between the glass transition temperature Tg and the onset temperature of crystallization Tx), which provides a large experimentally......
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Novel Phase Transition in BaPr2Mn2O7 Hiromi Nakano1,Naoki Kamegashira2 (1.Ryukoku University, Seta, Otsu 520-2194, Japan;2.Toyohashi University of Technology, Tenpaku-cho, Toyohashi 441-8580, Japan... homologous series AO(ABO3)2. In Pr-manganite, a novel phase transition was first observed in situ at 1040 K by a thermal transmission electron microscope. At 1040 K, reflections began to split along the c......
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to a glassy phase if crystallization is suppressed, namely a glass transition[1]. In terms of the free volume model, glass transition is regarded as a kinetic phenomenon depending on competition between... reduction increases, the crystallization onset temperature, peak temperature and the apparent activation energy of crystallization almost keep constant, while the glass transition temperature......
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glasses were altered and the crystallization was accelerated with Y2O3 addition, and only wollastonite as a main crystalline phase was precipitated. The volume fraction of crystalline phase and density... as a flux could promote crystallization. The glass transition temperature and the crystallization peak temperature decreased. The transformations of glass to β-quartz and of β-quartz to β-spodumene were also......
Crystallization kinetic characteristics of oxygen-induced I-phase and Zr2Cu phase in Zr65Cu27.5Al7.5 glassy alloy HE Lin(贺 林), HAN Zhen-hua(韩振华), JIANG Feng(江 峰), SUN Jun(孙 军) State Key...-diagrams were validated by XRD analyses and TEM observations. The crystallization kinetic characteristics of oxygen-induced I-phase and Zr2Cu phase in Zr65Cu27.5Al7.5 glassy alloy were discussed. It is found......
Phase separation and crystallization of La2O3 doped ZnO-B2O3-SiO2 glassMitang Wang1,2,Long Fang1,2,Mei Li1,2,Zhaogang Liu1,2,Yanhong Hu1,2,Xiaowei Zhang1,2,Wei Deng3,Ruhil Dongol41. School... the effect of the La2O3 on the phase separation and crystallization of ZnO-B2O3-SiO2 glass, after the occurence of the phase separation and crystallization of glasses by heat treatment......