Structure formation in martensitic Ni50Mn30Ga20 MSM alloy
Structure formation in martensitic Ni50Mn30Ga20 MSM alloy
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DOI：
10.1016/j.jallcom.2006.10.011
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发表时间：
2007-09
影响因子：
6.2
通讯作者：
U. Gaitzsch;M. Pötschke;S. Roth;N. Mattern;B. Rellinghaus;L. Schultz
中科院分区：
文献类型：
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作者：
U. Gaitzsch;M. Pötschke;S. Roth;N. Mattern;B. Rellinghaus;L. Schultz
已知Ni-Mn-Ga单晶显示出源自磁场诱导的孪晶边界运动的高达10%的应变。已知在可能的马氏体相中，5 M和7 M结构分别显示6%和10%的磁场诱导应变（MFIS）。对于Ni 50 Mn 30 Ga 20的成分，可以形成不同的马氏体结构，正如我们以前的工作所示。在室温下，可以发现7 M和NM结构。因此，研究了获得一种或另一种结构的制备路线。这项研究表明，热处理以及机械处理影响最终的结构。机械处理后观察到的结构变化是应力诱导的中间马氏体相变。这种应力诱导的NM相可以通过在奥氏体状态下退火而转变回7 M相。最后，对于Ni_（50）Mn_（30）Ga_（20）合金，通过适当的形变热处理，可以获得7 M或NM结构。
Ni–Mn–Ga single crystals are known for showing strains of up to 10% originating from magnetic field induced twin boundary motion. It is known that among the possible martensitic phases the 5M and 7M structure show magnetic-field-induced strain (MFIS) of 6% and 10%, respectively. For the composition Ni50Mn30Ga20different martensitic structures can develop, as it has been shown in our previous work. Both the 7M and NM structures can be found at room temperature. Therefore, the preparation routes to achieve one or the other structure were investigated. This study shows that thermal as well as mechanical treatments influence the final structure. The structural change observed after mechanical treatment is a stress-induced intermartensitic transformation. This stress-induced NM phase can be transformed back to the 7M phase by annealing in the austenite state. Finally, for the composition Ni50Mn30Ga20either the 7M or the NM structure can be achieved by appropriate thermomechanical treatment.