摘要
制备了伪双元合金Hf0.82Ta0.18Fe2。X射线衍射表明,合金为C14型Laves相结构,晶格常数为a=4.92133(3),c=8.0488(1)。在温度20K～380K范围内测量了穆斯堡尔谱。表明合金随温度存在两个磁相变点,一个从顺磁态(PM)到反铁磁态(AFM),相变温度为330K,另一个从反铁磁(AFM)到铁磁态(FM),相变温度约为180K。在AFM-FM相变点,6h位Fe原子自旋方向发生翻转,从沿c方向转向ab平面。相应地,2a位的Fe原子,在AFM态为顺磁性,经过该相变后,相应地呈现铁磁性排列。
The pseudobinary alloy Hf0.82Ta0.18Fe2 was prepared by arc melting and annealing technique. X-ray powder diffraction indicated a C14-type Laves phase structure with the crystal parameters a=4.92133（3）A and c=8.0488（1）A. The Mossbauer spectra were measured at different temperatures between 20 K and 380 K, and showed two magnetic phase transitions, one from paramagnetic state to antiferromagnetic state at about 330 K and the other from antiferromagnetic state to ferromagnetic state at about 180 K. The latter transition indicated a spin-reorientation for 6h site Fe atoms, thus, the Fe atom spin at 6h turn to ab plane from c axis. However, the Fe atoms at 2a also showed a magnetic moment in ferromagnetic state.
出处
《核技术》
EI
CAS
CSCD
北大核心
2007年第4期297-301,共5页
Nuclear Techniques
基金
国家自然科学基金(20050284003)资助
