Crystallization of high stable Zr55Al10Ni5Cu30bulk amorphous alloy
来源期刊：中国有色金属学报(英文版)2003年第z1期
论文作者：SHEN Jun (沈 军) SUN Jian-fei (孙剑飞) GAO Yu-lai (高玉来) WANG Gang (王 刚) XING Da-wei (邢大伟) CHEN De-Min (陈德民) ZHOU Bi-de (周彼德)
文章页码：59 - 63
Key words：bulk amorphous alloy; supercooled liquid; crystallization; JMA equation; kinetics
Abstract: The crystallization process of Zr55Al10Ni5Cu30 bulk amorphous alloy in the supercooled liquid region was investigated by differential scanning calorimetry in the mode of continuous heating and isothermal annealing. The parameters including glass transition temperature, onset crystallization temperature, and supercooled liquid region associated with the thermal stability of this alloy were measured. It is found that, in the case of continuous heating, both the onset and peak crystallization temperatures exhibit a strong dependence of the heating rate. And this relationship can be fitted by first order exponential decay equation. In addition, the isothermal kinetics was studied by Johnson-Mehl-Avrami (JMA) equation, and the Avrami exponents were calculated to be in the range of 2.0-5.0. On the basis of the Avrami exponents, it can be concluded that the crystallization process is mainly dominated by three-dimensional nucleation and growth.
SHEN Jun (沈 军), SUN Jian-fei (孙剑飞), GAO Yu-lai (高玉来), WANG Gang (王 刚), XING Da-wei (邢大伟), CHEN De-Min (陈德民), ZHOU Bi-de (周彼德)
(School of Materials Science and Engineering,
Harbin Institute of Technology, Harbin 150001, China)
Abstract:The crystallization process of Zr55Al10Ni5Cu30 bulk amorphous alloy in the supercooled liquid region was investigated by differential scanning calorimetry in the mode of continuous heating and isothermal annealing. The parameters including glass transition temperature, onset crystallization temperature, and supercooled liquid region associated with the thermal stability of this alloy were measured. It is found that, in the case of continuous heating, both the onset and peak crystallization temperatures exhibit a strong dependence of the heating rate. And this relationship can be fitted by first order exponential decay equation. In addition, the isothermal kinetics was studied by Johnson-Mehl-Avrami (JMA) equation, and the Avrami exponents were calculated to be in the range of 2.0-5.0. On the basis of the Avrami exponents, it can be concluded that the crystallization process is mainly dominated by three-dimensional nucleation and growth.
Key words:bulk amorphous alloy; supercooled liquid; crystallization; JMA equation; kinetics
