Itinerant-electron metamagnetic transition and giant magnetic entropy change in La_(0.8)Ce_(0.2)Fe_(11.4)Si_(1.6) compound  

作　　者：XU Chao LI Guodong LI Xiaowei WANG Ligang 

机构地区：[1]Department of Physics, Inner Mongolia University, Huhhot 010021,China [2]Department of Physics and Mathematics, HuaiHai Institute of Technology, Lianyungang 222005, China

出　　处：《Chinese Science Bulletin》2006年第17期2046-2049,共4页

基　　金：This work was supported by the National Natural Science Foundation of China （Grant No. 50164003）.

摘　　要：The crystal structure, itinerant-electron metamagnetic transition (IEMT) and magnetocaloric effect (MCE) in the iron-based rare-earth intermetallic compound La0.8Ce0.2Fe11.4Si1.6 have been investi- gated. The powder X-ray diffraction revealed that the ingot of La0.8Ce0.2Fe11.4Si1.6 annealed at 1373 K in vacuum for only 5 days could be crystallized in the cubic NaZn13-type structure. The La0.8Ce0.2Fe11.4Si1.6 compound exhibited giant values of the isothermal entropy change ?SM around the Curie temperature TC (about 186 K). And the maximum value ΔS M max is about 78.29 J/(kg·K) under a field change of 0—3 T, which can be calculated by the magnetization iso- therms around TC. Such a large MCE is attributed to the sharp change of magnetization and susceptibility around TC and the first-order magnetic transition of field-induced IEMT above TC.The crystal structure, itinerant-electron metamagnetic transition （IEMT） and magnetocaloric effect （MCE） in the iron-based rare-earth intermetallic compound La0.8Ce0.2Fe11.4Si1.6 have been investigated. The powder X-ray diffraction revealed that the ingot of La0.8Ce0.2Fe11.4Si1.6 annealed at 1373 K in vacuum for only 5 days could be crystallized in the cubic NaZn13-type structure. The La0.8Ce0.2Fe11.4Si1.6 compound exhibited giant values of the isothermal entropy change ASM around the Curie temperature Tc（about 186 K）. And the maximum value ｜△SM｜max is about 78.29J/（kg.K） under a field change of 0-3 T, which can be calculated by the magnetization isotherms around Tc. Such a large MCE is attributed to the sharp change of magnetization and susceptibility around Tc and the first-order magnetic transition of field-induced IEMT above Tc.

关 键 词：磁制冷材料 稀土 金属间化合物 磁热效应 La0.8Ce0.2Fe11.4Si1.6 

分 类 号：TB64[一般工业技术—制冷工程]