摘要
通过熔体快淬方法制备了LaFe11.5Si1.5Cx(x=0,0.1,0.2,0.3)系合金的快淬条带。采用X射线衍射分析仪、振动样品磁强计研究了C掺杂对La-Fe-Si合金在凝固过程以及随后热处理过程中的NaZn13型相形成及磁热性能的影响。结果表明:适量的C掺杂有利于凝固过程中NaZn13立方结构型的La(Fe,Si)13相的形成;C掺杂能有效地提高La(Fe,Si)13相的居里温度,当C含量由0增加到0.3时,合金的居里温度由210K升高到262K。合金居里温度的升高是由于掺杂的C原子占据了La(Fe,Si)13相中的间隙位置,使La(Fe,Si)13相晶格膨胀,Fe-Fe原子间铁磁交互作用增强。当C掺杂含量为0.2时,La-Fe-Si-C合金在1273K热处理2h时获得了最佳综合磁热性能,其居里温度(TC)为255K,最大等温磁熵变(ΔSM)为9.45J/(kg·K)(1.5T)。
LaFe11.5Si1.5Cx （x=0, 0.1, 0.2, 0. 3 ） ribbons were prepared by melt-spinning with cooper wheel. The influence of C atomic doping on the NaZn13-typephase formation and magnetocaloric properties during solidification and annealing was investigated by X-ray dimactometer （XRD） and vibrating sample magnetometer （VSM）. The results showed that： The doping of C atom was beneficial to the formation of La（Fe, Si）la phase with NaZn13-type; C doping into La（Fe, Si）13 phase can effectively improve the Curie temperature of La（Fe, Si）13 phase. When C content changed from 0 to 0. 3, the Curie temperature of LaFe11.5 Si1. 5Cx alloys increased from 210 K to 262 K. It is main reason that C atom accupied the interstitial position of La（Fe, Si）13 phase and lead to expand the lattice of cubic NaZn13type structure, therefore enhanced the interaction of Fe-Fe atoms. In addition, when x= 0. 2, LaFe11. 5 Si1. 5C, ribbons annealed at 1273 K for 2 h achieved the best magnetic properties and its maximum isothermal magnetic entropy change （ASM） reached values of 9.45 J/（kg . K） upon applied field of 1.5 T at Curie temperature （Tc） =255 K.
出处
《材料导报》
EI
CAS
CSCD
北大核心
2016年第8期104-108,121,共6页
Materials Reports
基金
国家自然科学基金(U1531120)
上海市教育委员会科研创新项目(12ZZ085)
上海市自然科学基金(13ZR1415300)
上海工程技术大学校级创新项目(14KY0521)
