摘要
磁制冷是一种利用材料的磁热效应进行制冷的新型制冷技术,相比于传统气体压缩制冷,因其绿色环保、高效节能等优点而备受关注。在众多磁相变合金材料中,人们对Mn_2Sb基亚铁磁相变合金研究甚少。文章研究了Cr取代Mn后亚铁磁性Mn_(2-x)Cr_xSb_(0.95)In_(0.05)(x=0.05,0.09,0.13)合金的磁性和磁热性能。室温XRD数据表明合金在室温附近以四角Cu_2Sb型结构为主相。由于反铁磁中有高磁响应,因此从XRD图谱中能观察到少量的铁磁MnSb杂相。随着温度的降低,在这些合金中,发生了亚铁磁到反铁磁的一级磁致弹性转变。同时,在亚铁磁区域观察到两个自旋重新取向转变。由于反铁磁-亚铁磁的转变过程中磁化强度突变,使得在Mn_(1.91)Cr_(0.09)Sb_(0.95)In_(0.05)合金中在0~10 k Oe的磁场变化中获得高达1.63 J/kg·K的大磁熵变。目前的研究可能有助于研究和开发新的磁性冷材料。
Magnetic refrigeration, based on the magnetocaloric effect （MCE） of magnetic materials, is a new kind of cooling technology. Due to the environment friendliness and energy efficiency compared with that of traditional gas compression refrigeration, magnetic refrigeration has attracted much attention. There are few researches to refer Mn2 Sb ferromagnetic phase transition alloy among many magnetic phase transition alloys. The magnetic and magnetocaloric properties are studied with Cr-substituted ferrimagnetic Mn2_x Crx Sb095 Inc.05 （x = 0. 05, 0. 09, 0. 13） alloys. A main phase with tetragonal CuESb-type structure is confirmed by XRD methodology at room temperature in these compounds. A small amount of MnSb impurity phase belonging to ferromagnet is also observed from the XRD patterns, and is responsible for the high magnetic response in the antiferromagnetic state. With decreasing temperature, Cr-substitution for Mn results in a first-order magnetoelastic transition from ferrimagnetic to antiferromagnetic state in these alloys. Simultaneously, two spin-reorientation transitions are observed during the ferrimagnetic region. Owing to the abrupt change in magnetization during the antiferromagnetic-ferrimagetic transition, large magnetic entropy change as high as 1.63 J/kg·K in Mn1.91Cr0.09Sb0.95In0.05 alloy under the magnetic field change of 0 - 10 kOe is obtained. The current studies may shed light on the research and development of new magnetic cooling materials.
作者
葛青
冯国芳
马胜灿
GE QingFENG GuofangMA Shengcan(Institute for Rare Earth Magnetic Materials and Devices(IREMMD),Jiangxi University of Science and Technology,Ganzhou 341000,ChinaInstitute of Engineering&Research,Jiangxi University of Science and Technology,Ganzhou 341000,China)
出处
《中国材料进展》
CSCD
北大核心
2017年第9期640-644,共5页
Materials China
基金
国家自然科学基金资助项目(51561023
51671097)
关键词
磁弹相变
亚铁磁
自旋重取向相变
磁热效应
磁熵变
magnetoelastic transition
ferrimagnetic
spin-reorientation transitions
magnetocaloric effect
magnetic entropy change
