Ni52Mn21+xGa27-x(x=0-5)磁性形状记忆合金的相变

研究了非化学计量成分的多晶Ni52Mn21+xGa27-x(x=0-5)系列合金的热弹性马氏体相变和磁相变.合金的马氏体相变温度Ms随Mn含量的增加而升高,当x＞4时,Ms已经升高到室温以上,而马氏体相变滞后△T随z的增大而减小;合金的磁相变温度TC随z增加而升高,但变化范围不大,在z＞2后,Tc保持在348 K左右.实验获得了一种具有实用前景的合金成分--Ni52Mn25Ga23合金,其马氏体相变温度在室温以上,相变滞后仅为5 K.

Phase Transformation in Ni52Mn21+xGa27-x(x =0-5) Magnetic Shape Memory Alloys

The martensitic and magnetic phase transformations in polycrystalline non-stoichiometric Ni52Mn21+xGa27-x(x=0-5) alloys were investigated. The experimental results show that the alloys exhibit ferromagnetic and thermo-elastic martensitic transformations. The martensitic transformation temperatures (Ms) increase with increasing Mn content and reach above room temperature when x >4. The martensitic transformation hysteresis (AT) decrease with increasing x. The magnetic phase transformation temperatures (Curie temperature TC) increase with an increase of x within a small range and keep around 348 K when x >2. In addition, an alloy composition of Ni52Mn25Ga23 with potential practicality was obtained, which has a higher martensitic transformation temperature than room temperature and a transformation hysteresis of only 5 K.