Abstract A new property of Heusler alloys known as shell-ferromagnetism is observed predominantly in NiMn-based Heusler alloys with X as Ga, Al, In and Sn. An antiferromagnetic-matrix/shell-ferromagnetic precipitate dual-phase generates from an anti-ferromagnetic initial structure with temper-annealing in an external magnetic field. The present study focuses on the magnetic and structural instabilities in CuMn-based Cu50Mn45Al5 Heusler alloy when temper-annealed under a magnetic field, as in NiMn-based Heusler alloys. The ternary Cu50Mn45Al5 Heusler alloy exhibits a cubic mictomagnetic structure in its initial state. Structural decomposition occurs during temper-annealing under a magnetic field from the initial state to a triple-phase composite alloy. The decomposed phases are identified to be cubic L2 1 Cu2MnAl, cubic L1 0 Cu50Mn50 and A13 β -Mn. As observed in shell-ferromagnetism, the ferromagnetic Cu2MnAl precipitates form in a mictomagnetic CuMn matrix with an additional β -Mn component.

中文翻译：

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微磁性 Cu50Mn45Al5 中的磁性和结构不稳定性对抗铁磁性沉淀物的形成

摘要 Heusler 合金的一种新特性，即壳铁磁性，主要在 X 为 Ga、Al、In 和 Sn 的 NiMn 基 Heusler 合金中观察到。反铁磁-基质/壳-铁磁沉淀双相从反铁磁初始结构产生，在外部磁场中进行回火退火。本研究的重点是在磁场下回火退火时 CuMn 基 Cu50Mn45Al5 Heusler 合金的磁性和结构不稳定性，如 NiMn 基 Heusler 合金。三元 Cu50Mn45Al5 Heusler 合金在其初始状态下呈现立方微磁结构。结构分解发生在磁场下从初始状态到三相复合合金的回火退火过程中。分解相被确定为立方 L2 1 Cu2MnAl、立方 L1 0 Cu50Mn50 和 A13 β -Mn。