摘要
采用X射线衍射分析、振动样品磁强计和差热分析研究了低温退火处理对Sm5Fe80Cu1Si5B3C2.5Zr3.5非晶合金晶化后纳米复合永磁体的组织结构、磁性能及晶化动力学的影响。结果表明,经400℃低温热处理后纳米复合合金中-αFe相和Sm2(Fe,Si)17Cx相的组织结构均产生了明显改变,晶粒尺寸分别从原始态(未经处理)的50.6 nm(-αFe相)和20.6 nm(Sm2(Fe,Si)17Cx相)改变为36.5和24.4 nm;体积分数分别从71.1%(-αFe相)和28.9%(Sm2(Fe,Si)17Cx相)改变为76.7%和23.3%;同时磁耦合性能明显增强。晶化动力学分析发现,低温热处理增大了非晶合金的短程有序范围,改变了原始态非晶合金中-αFe相和Sm2(Fe,Si)17Cx相的晶化行为,这是优化-αFe/Sm2(Fe,Si)17Cx复合纳米晶结构和提高磁耦合性能的根本原因。
The effects of preannealing treatment on the microstructure, nanocrystalline structure, magnetic properties and crystallization kinetics of α-Fe/Sm2Fe17Cx nanocomposite alloy was investigated by X-ray diffraction （ XRD ）, vibrating sample magnetometer （VSM） and differential thermal analysis （DTA）. The results showed that the microstructure parameters of α-Fe and Sm2 （Fe, Si ）17 C x phase changed obviously when the amorphous Sm5Fe80 Cu1Si5B3C2.5 Zr3.5 alloy was preannealed at 400 ℃ for 30 min. The grain size 50.6 nm for the α-Fe phase and 20.6 nm for Sm2（Fe, Si）17Cx phase in the alloy without preannealing treatment were varied to 36.5 and 24.4 nm in preannealling alloys, respectively. Also, the volume fraction 71.7% for α-Fe phase and 28.9% Sm2（Fe, Si）17 Cx phase were changed to 76.7% and 23.3% after preannealled at 400 ℃, respectively. The magnetic property of the preanealling alloy was enhanced due to increasing exchange coupling effect. It was found that, by the crystallization kinetics of amorphous alloys, the change of the microstructure parameter of amorphous alloy where the short-range order range increase could be essential for the formation of the α-Fe/ Sm2（Fe, Si）17Cx composite microstructure with uniform grain size and the increase of exchange coupling activation.
出处
《中国稀土学报》
CAS
CSCD
北大核心
2008年第2期167-172,共6页
Journal of the Chinese Society of Rare Earths
基金
国家自然科学基金(20571067)
浙江省计划(2006C14014)
浙江省重点科学计划(2007C11047)资助项目
关键词
非晶合金
纳米复合永磁体
晶化动力学
稀土
amorphous alloy
nanocomposite magnet
crystallization kinetics
rare earths
