摘要
本文研究了利用吸铸和短时间热处理方法制备的La0.8Ce0.2Fe11.4Si1.6B0.5化合物的微结构、磁性以及磁熵变性能。X射线衍射结果表明,与传统的长时间热处理方法(通常大于1周)相比,吸铸方法制备的La0.8Ce0.2Fe11.4Si1.6B0.5化合物只需经过1373K真空退火处理2h后,全部转变为单相立方NaZn13型晶体结构。磁测量表明,样品具有较小的热滞和磁滞,B添加使居里温度TC提高到197K,最大磁熵变为15.3J/(kg.K)。这些研究说明了吸铸短时退火是一种制备磁制冷材料的优异方法,该方法制备的La0.8Ce0.2Fe11.4Si1.6B0.5化合物是一种优良的磁制冷工质。
The crystal structure,magnetic properties and magnetocaloric effect （MCE） of La0.8Ce0.2Fe11.4Si1.6B0.5 alloy prepared by copper mould casting （CMC） and short -time annealign,have been investigated. It is revealed that the cubic NaZn13-type structure is formed in La0.8Ce0.2Fe11.4Si1.6B0.3 alloy annealed only 2 h at 1373 K. Moreover,the annealed alloy exhibits relatively lower thermal lag and magnetic hysteresis. The addition of B leads to an increase of Curie temperature （TC）.. The maximum value of —ΔSM—～15.3 J/kg.K was achieved in the annealed compound around its TC of 197 K. The good MCE performance indicates that CMC and subsequently short-time annealing is a good method to prepare magnetic refrigeration materials.
出处
《福建师大福清分校学报》
2009年第B12期75-78,共4页
Journal of Fuqing Branch of Fujian Normal University
基金
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)
福建师范大学本科生课外科技计划项目(BKL2009-011)
关键词
磁熵变
吸铸
居里温度
NaZn13相结构
Magnetic entropy change
Copper mould casting
Curie temperature
NaZn13phase
