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Ｎｉ２ＭｎＧａ晶体同时具有强铁磁性、大磁致伸缩、温控和磁控形状记忆效应，其磁控形状记忆效应的响应频率接近压电陶瓷，输出应变和应力接近温控形状记忆合金，是近年来发现的一类新型功能晶体．Ｎｉ２ＭｐＧａ晶体７７Ｋ时在［００１］方向，仅２ＭＰａ的预应力即可产生５％的温控可回复应变，已接近 ＴｉＮｉ合金 ６％～８％的可回复应变量；非化学剂量的 Ｎｉ。ＭｎＧａ晶体室温条件下在［００１］方向， ６ ｈＯｅ外磁场已诱发产生 ０．３１％的输出应变，远超过巨磁致伸缩材料Ｔｅｒｆｅｎｏｌ－Ｄ输出应变０．１７％的水平．由于该晶体在磁场控制下表现出的大输出应变和应力，以及响应频率快和可精确控制的综合特性，使其可能在声纳、微位移器、线性马达、微波器件、振动和噪声控制、机器人和智能结构等诸多领域有重要应用，成为未来新一代驱动器和传感器材料．本文综述了Ｎｉ２ＭｎＧａ单晶的基本性能、磁控形状记忆效应的机理、本质以及影响性能的因素等。
Ni2MnGa crystal has both ferromagnetism, giant magnetostriction, temperature control and magnetron shape memory effect. The response frequency of magneto-shape shape memory effect is close to that of piezoelectric ceramic, and the output strain and stress are close to that of temperature-controlled shape memory alloy. In recent years Found a new type of functional crystal. Ni2MpGa crystal at 77K in the [001] direction, only 2MPa prestress can produce 5% temperature-controlled recoverable strain, has been close to TiNi alloy 6% to 8% of the recoverable strain; non-chemical dose of Ni. In the [001] direction, the magnetic field of MnGa crystal at 6 h Oe induced a 0.31% output strain at room temperature, far exceeding the 0.17% output strain of the giant magnetostrictive material Terfenol-D. Due to its large output strain and stress under magnetic field control and the combination of fast response and precise control, the crystal may be used in sonar, micropositioning, linear motors, microwave devices, vibration and noise control, Robotics and intelligent structures and many other areas have important applications, a new generation of future drive and sensor materials. In this paper, the basic properties of Ni2MnGa single crystal, the mechanism and nature of magneto-shape memory effect, and the factors affecting the performance are summarized.