Nb对非晶态Fe-Co-Nd-B合金的晶化动力学的影响  

EFFECT OF Nb ON CRYSTALLIZATION KINETICS OF Fe-Co-Nd-B AMORPHOUS ALLOYS

作　　者：徐民[1,2] 易军[1] 全明秀[2] 王沿东[1] 左良[1] 

机构地区：[1]东北大学材料各向异性与织构教育部重点实验室,沈阳110004 [2]中国科学院金属研究所沈阳材料科学国家联合实验室,沈阳110016

出　　处：《金属学报》2009年第1期91-96,共6页Acta Metallurgica Sinica

基　　金：国家自然科学基金资助项目50471075~~

摘　　要：在Fe-Co-Nd-B非晶合金中添加4%的Nb(原子分数)可延迟其晶化过程,提高晶化温度,并使其热稳定性显著提高.Nb抑制Fe_3B晶化相的形核,但促进Fe_(23)B_6相的形核及长大.Nb可使晶化相的平均晶粒尺寸从30—60 nm减至14—20 nm.Nb使由初始晶化温度计算的晶化激活能明显降低.Fe-Co-Nd-B合金中,α-Fe(Co),Fe_3B和Nd_2(Fe,Co)_(14)B晶化相的形核过程要难于长大过程,而加Nb后α-Fe(Co),Fe_(23)B_6和Nd_2(Fe,Co)_(14)B晶化相的长大过程要难于形核过程,但Nb基本未改变晶化相的形核及长大机制.非晶合金的晶化主要是一维界面控制的形核以及形核率随时间减小的三维长大过程.The addition of 4% niobium in Fe Co Nb B amorphous alloy may retard the crystallization process, raise the crystallized temperature and enhance the thermal stability. The nucleation of Fe3B crystallized phase is checked while the nucleation and growth of Fe23B6 phase is promoted. The average grain sizes can be reduced from 30-60 nm to about 14-20 nm. The crystallization activation energy calculated by the onset crystallization temperatures decreases obviously. The nucleation process of α-Fe（Co）, Fe3B and Nd2（Fe, Co）14B phases is more difficult than the growth process, while the growth process of α-Fe（Co）, Fe23B6 and Nd2（Fe, Co）14B phases is more difficult than the nucleation process caused by the addition of niobium. However, the mechanism of the nucleation and growth of the crystallized phases is almost unchanged. The crystallization process is mainly dominated by one-dimensional nucleation and three dimensional growth with decreasing nucleation rate.

关 键 词：铁基非晶合金 晶化动力学 晶化激活能 局域Avrami指数 

分 类 号：TG139[一般工业技术—材料科学与工程]