利用覆盖渣技术在非真空条件下成功制备出了直径为3mm的Zr55Ni5Al10Cu30块体非晶合金。采用差示扫描量热法(DSC),将Johnson-Mehl-Avrami理论拓展应用于非晶合金的非等温晶化过程研究。结果表明,Zr55Ni5Al10Cu30块体非晶合金的连续升温晶化过程Avrami指数及形核率随升温速率的升高而呈下降趋势,同时随晶化过程进行呈先增加后减小的规律。Avrami指数最大值出现在晶化体积分数0.3~0.4之间,在低升温速率下Zr55Ni5Al10Cu30块体非晶合金部分晶化过程出现三维形核界面控制长大的形式。
Bulk amorphous alloy Zr55Ni5Al10Cu30 with the diameter of 3 mm was prepared by covering slag technology combing copper-mold casting under non-vacuum melting condition.Different scanning calorimeter(DSC) and Johnson-Mehl-Avrami theory were used to investigate non-isothermal crystallization kinetics of Zr55Ni5Al10Cu30 bulk amorphous alloy.Results show that Avrami exponent and nucleation rate during continuously rising temperature crystallization decrease with the rising of heating rate,and increase at first with the crystallization process proceeding and then decrease.Avrami exponent reaches its maximum value between 0.3~0.4 of crystallization volume fraction.At low heating rate,there are some processes of crystallization governed by three-dimensional interface-controlled growth.