CeFe10．5Si2．5金属间化合物晶体结构、磁性和磁熵变特性研究  

Crystal Structure,Magnetic Properties and Magnetic Entropy Change of Intermetallic Compounds CeFe_(10.5)Si_(2.5 )

作　　者：徐超[1] 刘学东[1] 李晓伟[2] 李国栋[3] 

机构地区：[1]淮海工学院数理科学系,江苏连云港222005 [2]内蒙古科技大学材料与冶金学院,内蒙古包头014010 [3]内蒙古大学物理系稀土材料重点实验室,内蒙古呼和浩特010021

出　　处：《中国稀土学报》2008年第2期178-181,共4页Journal of the Chinese Society of Rare Earths

基　　金：淮海工学院引进人才资助项目(KQ07078);国家自然科学基金资助项目(50164003)

摘　　要：通过X射线衍射和磁性测量等手段对金属间化合物CeFe10.5Si2.5的晶体结构、磁性以及磁熵变进行了研究。结果表明,经过对铸态样品进行12 h退火所得的金属间化合物CeFe10.5Si2.5晶体为单相立方NaZn13型结构;在1.5 T外磁场下居里温度TC^206 K附近的最大等温磁熵变为10.7 J.kg-1.K-1,并随着外磁场的增大而迅速增大;从Arrott曲线中可以看出,在此化合物中没有明显的巡游电子变磁转变特性,但从低磁场下的热磁曲线可知,磁化强度在居里温度处发生陡峭的变化,这应该是该化合物获得大磁熵变的原因。The crystal structure, magnetic properties and magnetic entropy change of CeFe10.5Si2.5 were investigated by X-ray powder diffraction and magnetic measurements. The X-ray diffraction pattern revealed that the compound annealed for 12 h remains the single phase cubic NaZnla-type structure. The maximum value │△SM│ max was 10.7 J·kg^-1 ·K^-1 under a field change of 0 - 1.5 T, which could be calculated by themagnetization isotherms around Tc - 206 K, and it increased rapidly as the external magnetic field increased. The Arrott plot showed that the itinerantelectron metamagnetic was not evident. It could be seen from the thermomagnetic curve that the magnetization changed sharply at Tc, which was attributed to the large magnetocaloric effect.

关 键 词：等温磁熵变 NaZn13-型金属间化合物 巡游电子变磁转变 磁致冷材料 稀土 

分 类 号：O482.6[理学—固体物理]