非晶Fe_(77.5)Si_(8.5)B_(14)合金晶化动力学的非等温方法研究  

Non-isothermal Study of Crystallization Kineticsof Fe_(77.5)Si_(8.5)B_(14) Amorphous Alloy

作　　者：陆伟[1] 严彪[1] 李志国[2] 黄文旵[1] 

机构地区：[1]同济大学材料科学与工程学院,上海200092 [2]同济大学物理系,上海200092

出　　处：《同济大学学报（自然科学版）》2005年第4期498-501,共4页Journal of Tongji University:Natural Science

基　　金：上海市科学技术发展基金资助项目(0252nm054;0352nm057)

摘　　要：利用非等温差示扫描热分析法(DSC)研究了非晶Fe_(77.5)Si_(8.5)B_(14)合金的晶化动力学.不同升温速率的DSC曲线表明非晶Fe_(77.5)Si_(8.5)B_(14)合金的晶化过程为两步晶化.通过对不同升温速率的DSC曲线的分析,计算了两个析晶峰的晶化表观激活能E1(388.2kJ·mol-1)和E2(339.0kJ·mol-1),以及两个析晶峰的Avrami指数n1(1.7)和n2(3.3).根据动力学参数分析了非晶Fe_(77.5)Si_(8.5)B_(14)合金的析晶机理晶化峰1的成核类型为均匀成核,晶粒生长为扩散控制的一维生长和二维生长;晶化峰2为整体析晶,晶粒生长以界面控制的二维生长和三维生长为主.最后结合表观激活能计算了两个析晶反应的频率因子ν1(4.05×1025)和ν2(1.14×1021).The crystallization kinetics of the Fe_~77.5 Si_~8.5 B_~14 amorphous alloy was investigated by differential scanning calorimetry (DSC).According to the DSC curves at different heating rates,two well separated crystallization peaks were always observed.On the basis of the modified Kissinger law and the classical (Johmson-Mehl-Avrami) function,the nucleation and growth kinetic parameters,such as the Avrami exponent n (n_1=1.7 for peak 1 and n_2=3.3 for peak 2),the apparent activation energy E (E_1=388.2 ~kJ·mol^-1 and E_2=339.0 kJ·mol^-1 ) and the frequency factor ν(ν_1=4.05×10~25 ,ν_2=1.14×10~21 ),were determined for the two crystallization peaks.For the primary crystallization (R1),the crystallization mechanism is surface crystallization with one and two dimensional nucleation graining growth controlled by interface at constant nucleation rate.For the secondary crystallization (R2),the crystallization mechanism is bulk crystallization with two and three dimensional nucleation graining growth controlled by diffusion.

关 键 词：晶化动力学 非晶FeSiB合金 非等温差示扫描热分析 

分 类 号：TG139.8[一般工业技术—材料科学与工程]