不同工艺和原料对Mn_(1.2)Fe_(0.8)P_(0.48)Si_(0.52)化合物磁热效应的影响  

Influence of Different Preparation Techniques and Raw Materials on Magnetocaloric Effect in Mn_(1.2)Fe_(0.8)P_(0.48)Si_(0.52) Compound

作　　者：耿遥祥[1] 特古斯[1] 毕力格[1] 王伟[1] 哈斯朝鲁[1] 松林[1] 

机构地区：[1]内蒙古师范大学内蒙古自治区功能材料物理与化学重点实验室,内蒙古呼和浩特010022

出　　处：《中国稀土学报》2011年第3期266-270,共5页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金(50961010);内蒙古自然科学重点项目(20080404Zd01)资助

摘　　要：用不同的工艺和原料制备了3个名义成分相同的Mn1.2Fe0.8P0.48S i0.52化合物。X射线衍射结果表明,3个化合物均为Fe2P型六角结构（空间群为P-62m）,并且存在少量的（Fe,Mn）3S i相。通过磁性测量发现,3个样品的居里温度有所不同,但是都在室温附近（270~290 K）。以Fe2P为原料制备的化合物具有较大的磁熵变,在1.5 T的磁场变化下其最大磁熵变为13.6 J.（kg.K）-1。以行星样品球磨机制备的化合物具有较小的热滞,最小热滞为6.7 K。这些表明不同的制备工艺和原料对化合物的居里温度、热滞和磁熵变都具有一定的影响。同时低成本的原料、简单的制备工艺、较小的热滞和较大的磁熵变使得Mn1.2Fe0.8P0.48S i0.52化合物成为一种理想的室温磁致冷候选材料。The three samples of Mn1.2Fe0.8P0.48Si0.52 were prepared by different preparation techniques and raw materials.The powder X-ray diffraction patterns showed that all samples crystallized in the hexagonal Fe2P-type structure（space group P-62m）,with minor（Fe,Mn）3Si as a second phase.The magnetic measurements showed that the Curie temperatures of three samples were different,but they were near room temperature.The samples with Fe2P as raw materials exhibited large magnetic entropy change,and the maximum magnetic entropy change of samples was about 13.6 J ·（kg · K）-1 in a field change of 1.5 T.The samples prepared by plate high energy ball milling possessed smaller thermal hysteresis,and the minimum thermal hysteresis was about 6.7 K.The different preparation techniques and raw materials had certain influence on the Curie temperature,thermal hysteresis and magnetic entropy change of Mn1.2Fe0.8P0.48Si0.52 compound.The low-cost raw materials,simple preparation techniques,smaller thermal hysteresis and large magnetic entropy change made compound Mn1.2Fe0.8P0.48Si0.52 an excellent candidate material for room-temperature magnetic refrigeration applications.

关 键 词：磁致冷 居里温度 热滞 磁熵变 稀土 

分 类 号：TG156[金属学及工艺—热处理] TG115.22[金属学及工艺—金属学]