金属玻璃的晶化动力学(英文)

On the Crystallization Kinetics in Metallic Glasses

用差示扫描量热计(DSC)研究晶化动力学表明金属玻璃Pd_(80_B_1Si_(16)的相变过程分二步进行。本文建立了最大晶化速率(dx/dt)_p。Avrami指数n及对应晶化峰值温度的反应率常数K_p之间关系式为(dx/dt)_p=0.37nk。利用最大反应率方程可计算金属玻璃Pd_(80)B_1Si_(16)二阶段的晶化动力学参数:由MSI阶段到MSⅡ阶段,激活能E由98.2kcal/克分子增加到109.1kcal/克分子;Avrami指数n由1.1～1.2增加到1.9～2.1。

The investigation of the crystallization kinetics of Pd_(80) B_1Si_(16) glass by differential scanningcalorimeter (DSC) indicated a two-stage crystallization process during phase change. A rela-tionship between the maximum crystallization rate(dx/dt)_p. the Avrami exponent n and therate constant K_p at the peak temperature of crystallization was established: (dx/dt)_p=0.37nK_pBy means of this equation defined as the maximum reaction rate equation we were able to cal-culate the parameters of crystallization kinetics of Pd_(80) B_1Si_(16) glass for both crystallizationstages. The activation energy increase from E=98. 2kcal/mol. at the MSI stage to E =109. 1kcal/mol. at the MSII stage. The Avrami exponent has essentially doubled its value fromn =1.1～1.2 at the MSI stage to n=1.9～2.1 at the MSII stage.