快淬法制备La_(0.8)Ce_(0.2)Fe_(11.4)Si_(1.6)合金的磁熵变研究  

Improvement of Magnetic Entropy Change of La_(0.8)Ce_(0.2)Fe_(11.4)Si_(1.6) Compounds Prepared by Rapid Quenching

作　　者：林志平[1] 李山东[1,2] 林志强[3] 

机构地区：[1]福建师范大学物理与光电信息科技学院物理系,福建福州350007 [2]南京大学固体微结构国家重点实验室,江苏南京210093 [3]北京邮电大学理学院,北京100876

出　　处：《中国稀土学报》2010年第3期343-346,共4页Journal of the Chinese Society of Rare Earths

基　　金：教育部新世纪优秀人才支持计划项目(NCET-08-0631);国家自然科学基金(10504010);福建省科技厅重点项目(2009H0019);福建师范大学优秀青年骨干教师培养基金(2008100217)资助

摘　　要：为了探求La系磁熵变材料的短时退火工艺,利用两种方法制备了磁制冷材料La0.8Ce0.2Fe11.4Si1.6合金,其一为将电弧熔炼合金退火5天(样品A),其二为将合金利用铜模铸造方法得到快淬样品,再退火2 h(样品B)。X射线衍射表明,样品A和B主相为NaZn13相结构。通过对比发现,尽管样品A的最大磁熵变值大于样品B的,但样品B在制冷温区和制冷能力方面优于样品A。因此,快淬加短时间热处理可以大大节省时间和能量,是一种制备La0.8Ce0.2Fe11.4Si1.6磁制冷材料的高效且性能优越的方法。In order to explore a short time annealing method for La series magnetic refrigerant materials.La0.8Ce0.2Fe11.4Si1.6 alloys were prepared by two different methods,one was arc-melting and subsequently annealed for 5 d（refers to sample A）,and the other was rapid quenching by copper mould casting and subsequently annealing for 2 h（refers to sample B）.The XRD results showed that the sample A and B were mainly composed of NaZn13-type phase.Comparing sample B with sample A,it was found that although the maximum magnetic entropy change of sample B was smaller than that of sample A,the working temperature span of sample B was broader than that of sample A.Moreover,the refrigerant capacity of sample B was larger than that of sample A.These facts suggested that rapid quenching might save much time and energy.It was a good method for the preparation of La0.8Ce0.2Fe11.4Si1.6 magnetocaloric material.

关 键 词：磁熵变 快淬 制冷能力 NaZn13 稀土 

分 类 号：TM271[一般工业技术—材料科学与工程] O482.54[电气工程—电工理论与新技术]