The structural and magnetic properties of Mn2−xFexNiGa Heusler alloys
The structural and magnetic properties of Mn2−xFexNiGa Heusler alloys
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DOI：
10.1063/1.3269722
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发表时间：
2010-01
影响因子：
3.2
通讯作者：
Hongzhi Luo;F. Meng;Zhong-Ying Feng;Yangxiang Li;Wei Zhu;Guangheng Wu;Xiaoxi Zhu;Chengbao Jiang-Chengbao-Jia
中科院分区：
文献类型：
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作者：
Hongzhi Luo;F. Meng;Zhong-Ying Feng;Yangxiang Li;Wei Zhu;Guangheng Wu;Xiaoxi Zhu;Chengbao Jiang-Chengbao-Jia
研究了Fe替代对Mn2NiGa的相变和磁性能的影响。在Mn2−xFexNiGa(x=0~0.6)中获得了单一的体心立方相。随着Fe对Mn的取代，晶格常数逐渐减小。当x=0-0.3时，可以观察到马氏体相变。马氏体相变温度和奥氏体相变温度均随Fe含量的增加而单调下降，这与Ni-Mn-Ga系中常见的电子浓度依赖关系不同。随着Fe的掺杂，Mn2−xFexNiGa在奥氏体相和马氏体相中的饱和磁化强度Ms均明显增加，而Tc的变化趋势则相反。理论计算表明，奥氏体相和马氏体相均为亚铁磁体。四方形变后，铁磁矩由正变负，导致饱和磁化强度降低。
The effect of Fe substitution on the phase transformation and magnetic properties of Mn2NiGa has been studied. A single bcc phase was obtained in Mn2−xFexNiGa (x=0–0.6). With the substitution of Fe for Mn, the lattice constant decreases gradually. The martensitic transformation can be observed when x=0–0.3. Both the martensitic transformation and austenitic transformation temperatures decrease monotonically with increasing Fe content, which is different from common electron concentration dependence in Ni–Mn–Ga system. The saturation magnetizations Ms of Mn2−xFexNiGa in both austenitic and martensitic phases increase obviously with the doping of Fe, while the variation of TC shows an opposite tendency. Theoretical calculations indicate that both austenitic and martensitic phases are ferrimagnets. The Fe moment varies from positive to negative after the tetragonal distortion, which leads to the decrease of the saturation magnetization.