Comparative study of non-isothermal crystallization kinetics between Fe80P13C7 bulk metallic glass and melt-spun glassy ribbon
Comparative study of non-isothermal crystallization kinetics between Fe80P13C7 bulk metallic glass and melt-spun glassy ribbon
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Fe80P13C7块体金属玻璃与熔纺玻带非等温结晶动力学对比研究
DOI：
10.1016/j.jallcom.2012.06.016
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发表时间：
2012-11
影响因子：
6.2
通讯作者：
Li, Qiang
中科院分区：
文献类型：
--
作者：
Wang, Yan;Xu, Kai;Li, Qiang
用差示扫描量热法研究了块状和快淬条状Fe80P13C7玻璃合金的热行为和非等温结晶动力学。基辛格法测得带状样品和块体样品第一次晶化事件的表观活化能E分别为432±17kJ/mol和529±26kJ/mol，Ozawa法分别为421±17kJ/mol和514±26kJ/mol。结果表明，较大的表观活化能E可归因于较小的过冷液相态自由体积。用非等温法研究了块体和带状样品中第一结晶事件的结晶动力学，并求出了第一结晶峰的局部Avrami指数，揭示了结晶机理。在第一次晶化过程中，块体样品的局域Avrami指数在整个过程中均小于1.5，这意味着晶核的生长是扩散控制的结晶机制。而带状样品的局域Avrami指数大多在1.5-2.5之间，这意味着晶化机制是扩散控制的初始晶型生长，同时形核率随着时间的延长而减小。块体样品和带状样品第一次晶化事件的局域Avrami指数的差异表明，在过冷液态下，块体样品的短程有序度高于带状样品。这些结果清楚地表明，Fe80P13C7玻璃合金块体和带状样品第一次晶化行为的差异是由于它们的过冷液态性质不同造成的，这与样品的制备状态有关。
Differential scanning calorimetry was used to investigate the thermal behavior and non-isothermal crystallization kinetics of Fe80P13C7glassy alloy in the forms of both bulk rod and the melt-spun ribbon. The apparent activation energy E of the first crystallization event for the ribbon and bulk samples are determined to be 432±17kJ/mol and 529±26kJ/mol, respectively, by Kissinger method, and 421±17kJ/mol and 514±26kJ/mol, respectively, by Ozawa method. It is proposed that larger the apparent activation energy E in the bulk sample may be ascribed to less amount of free volume in the supercooled liquid state of the bulk sample. The crystallization kinetics of the first crystallization event in the bulk and ribbon samples has been studied by non-isothermal approach and the local Avrami exponent for the first crystallization peak is evolved to reveal the crystallization mechanism. The local Avrami exponent of the bulk sample is less than 1.5 in the whole process for the first crystallization event, which means the crystallization mechanism of diffusion-controlled growth of pre-existing nuclei. While the local Avrami exponent for the ribbon sample is in the range of 1.5–2.5 in most cases, which means the crystallization mechanism is diffusion-controlled growth of the initial crystal type, at the same time, along with the nucleation rate decreases with time. The difference in the local Avrami exponent for the first crystallization event between the bulk and ribbon sample indicates that there are higher degree of short-range order in the bulk sample than that in the ribbon sample in the supercooled liquid state. These results distinctly indicate that the difference of crystallization behavior for the first crystallization event between the bulk and ribbon samples of Fe80P13C7glassy alloy results from the difference nature in their supercooled liquid states which is related to the as-prepared state of samples.
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影响因子：
4
作者：
B. Adnađević;B. Janković;D. Minic
通讯作者：
B. Adnađević;B. Janković;D. Minic
影响因子：
7.4
作者：
KISSINGER, HE
通讯作者：
KISSINGER, HE
影响因子：
3
作者：
M. P. Trujillo;A. Orozco;M. Casas-Ruiz;R. Ligero;R. Jiménez-Garay
通讯作者：
M. P. Trujillo;A. Orozco;M. Casas-Ruiz;R. Ligero;R. Jiménez-Garay
影响因子：
3
作者：
NAKAMURA, K;WATANABE, T;KATAYAMA, K
通讯作者：
KATAYAMA, K
影响因子：
4.4
作者：
Qiang Li;Jin-feng Li;P. Gong;K. Yao;Jin Gao;Hongxiang Li
通讯作者：
Qiang Li;Jin-feng Li;P. Gong;K. Yao;Jin Gao;Hongxiang Li