Abstract Influence of Fe substitution for Ni on the magnetic properties and martensitic transformation was investigated theoretically in Heusler alloys Ni2Mn1.5Z0.5 (Z = In, Sb). Fe-doping does not change the general magnetic structure of Ni2Mn1.5Z0.5. In both Ni2Mn15In0.5 and Ni1.75Fe0.25Mn1.5In0.5 the austenitic phase is ferromagnetic and martensitic phase is antiferromagnetic, which leads to the large ΔM observed experimentally. But in Ni2Mn1.5Sb0.5 and Ni1.75Fe0.25Mn1.5Sb0.5, the antiferromagnetic state is stable in both austenite and martensite. This difference is mainly related to the different atomic radii of In and Sb, which change the distance between Mn (B) and Mn (D). Parallel or antiparallel coupled Mn moments determine the magnetic properties of these alloys. But the partial moment of Fe is large and its direction reverses after martensitic transformation, which makes it a possible way to adjust the magnetic properties of MSMAs. Calculation also suggests that the substitution of Fe for Ni can lower the martensitic transition driving force and lead to the decrease of phase transition temperature. These results agree well with preceding experimental results and make reasonable explanation for them.

中文翻译：

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Fe掺杂对Ni Mn In和Ni Mn Sb合金磁结构和马氏体转变的影响

摘要 从理论上研究了 Fe 替代 Ni 对 Heusler 合金 Ni2Mn1.5Z0.5 (Z = In, Sb) 磁性能和马氏体转变的影响。Fe掺杂不会改变Ni2Mn1.5Z0.5的一般磁结构。在 Ni2Mn15In0.5 和 Ni1.75Fe0.25Mn1.5In0.5 中，奥氏体相是铁磁性的，而马氏体相是反铁磁性的，这导致实验观察到的大 ΔM。但在 Ni2Mn1.5Sb0.5 和 Ni1.75Fe0.25Mn1.5Sb0.5 中，反铁磁状态在奥氏体和马氏体中都是稳定的。这种差异主要与In和Sb的原子半径不同，改变了Mn(B)和Mn(D)之间的距离有关。平行或反平行耦合的 Mn 矩决定了这些合金的磁性。但Fe的偏矩较大，且经过马氏体相变后方向相反，这为调节MSMAs的磁性能提供了可能。计算还表明，Fe 替代 Ni 可以降低马氏体转变驱动力并导致相变温度降低。这些结果与前面的实验结果非常吻合，并对其做出了合理的解释。