摘要
用非自耗真空电弧炉制备LaMn2Ge2合金,采用X射线衍射研究了合金的结构,LaMn2Ge2在常温下具有ThCr2Si2-型晶体结构,空间群为I4/mmm。利用振动样品磁强计测量合金的磁性能,根据升降温的磁化曲线所确定的合金发生反铁磁-铁磁相变温度有4.3K的滞后,居里温度约320K,具有一级相变的典型特征。通过不同温度的磁化曲线结果,计算得LaMn2Ge2在1.43×106A/m外场变化下居里温度附近的最大磁熵变为1.42J/kg·K。
LaMn2Ge2 was prepared by arc-melting method, the crystal structure and magnetic properties were investigated by X-ray powder diffraction and vibrating sample magnetometer, respectively. At room temperature, LaMn2Ge2 has in ThCr2Si2-type structure with space group I4/mmm. The Curie temperature of anti ferromagnetic-ferromagnetic transition is about 320 K with a hysteresis of about 4.3 K and the intermetallic is possessed of a typical first-order phase transition. The magnetic entropy change is obtained based on the magnetization isotherms at different temperatures. The maximal magnetic entropy of the LaMn2Ge2, with the field changes from 0 to 1.43 × 10^6 A/m, reaches 1.42 J/kg. K near its Curie temperature.
出处
《稀有金属材料与工程》
SCIE
EI
CAS
CSCD
北大核心
2006年第11期1803-1805,共3页
Rare Metal Materials and Engineering
基金
国家"863"资助项目(2002AA324010)
关键词
LaMn2Ge2
磁相变
磁熵变
居里温度
LaMn2Ge2
magnetic phase transition
magnetic entropy change
curie temperature