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用四探针电阻测量法研究Zr55 Cu30 Al10 Ni5非晶合金的等温晶化行为.该非晶合金的晶化过程只包括一个晶化阶段.在晶化过程中,随着等温温度的升高,孕育期会减小,且完成晶化所需的时间变短,726,731和736 K时的孕育期分别为1120,935和335 s,完成晶化的时间分别为3500,2620和1500 s.通过电阻随等温时间的变化曲线可以得到某一时刻的晶化体积分数X(t),不同温度下晶化体积分数随等温时间的变化曲线均呈典型的“S”型.等温晶化动力学行为符合Johnson-Mehl-Avrami模型.在726,731和736 K等温时,Avrami指数分别为2.5,1.5和1.7,均在1.5和2.5之间,表明晶化过程是形核速率减小的长大过程.随着等温时间的增加,起初局域Avrami指数几乎不变,当等温时间增加到一定程度时,局域Avrami指数开始逐渐减小.随着等温温度的升高,局域Avrami指数降低的越明显.“,”The crystallization behavior of the Zr 55 Cu30 Al10 Ni5 bulk metallic glass was investigated using isothermal electrical resistivity measurement at different temperatures in the super-cooled liquid region .The crystallization process was a single step phase transforma-tion.In the process of isothermal crystallization , incubation period decreased with the increase of the isothermal annealing temperature . The time for the resistivity to reach a stable value decreased with the increase of the isothermal temperature .The time were 3500 , 2620, and 1500 s at 726, 731, and 736 K, respectively.The crystallized volume fraction X(t) at a time during isothermal heating could be obtained from the curve of normalized resistivity along with the change of isothermal time .The curves at different temperature presented a typical “S” type.The isothermal crystallization showed that the kinetics could be described by Johnson -Mehl-Avrami mod-el.The Avrami exponents at 726, 731, and 736 K were 2.5, 1.5, and 1.7, respectively, indicating that the crystallization processes were diffusion controlled with nucleation decreasing .With the increase of isothermal time , the local Avrami exponent almost remained the same at first.When the isothermal time increased to a certain extent , the local Avrami exponent began to decrease gradually .And the higher the isothermal temperature was , the more obviously the local Avrami exponent decreased .