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与温度驱动形状记忆的缓慢响应及磁场驱动形状记忆的巨大体积相比较,电场驱动形状记忆具有响应快和体积小的优点。但是,基于传统反压电效应的电场驱动形状记忆由于变形量较小而收到限制。本研究表明,通过运用基于点缺陷短程序对称性遵循的普适性原理的可逆畴翻转机制,可以在铁电马氏体中获得巨大的电致形状记忆效应;其产生的变形量理论上是反压电效应所产生变形量的几十倍。采用原位畴观察实验给出了可逆畴翻转的直接证据。并且,在铁电多晶陶瓷中也获得了这种大的电致形状记忆效应。这种效应在很宽的频率范围内都很稳定,在疲劳测试中也显示了很好的可靠性。运用这一新的电致形状效应有望制备出新一代非线性驱动器材料。
Compared with the slow response of temperature driven shape memory and the huge volume of magnetic field driven shape memory, electric field driven shape memory has the advantages of fast response and small size. However, the electric field driven shape memory based on the traditional backpressing effect is limited due to the small amount of deformation. This study shows that by using the reversible domain inversion mechanism based on the universality principle that the symmetry of point defects follows a short program, a huge electromochromic memory effect can be obtained in ferroelectric martensite; the amount of deformation caused by it is theoretically Anti-piezoelectric effect of deformation caused by several times. The direct evidence of reversible domain inversion is given by using in situ domain observations. Also, this large electrosurgical shape memory effect is also obtained in ferroelectric polycrystalline ceramics. This effect is stable over a wide frequency range and shows good reliability in fatigue tests. It is expected that a new generation of non-linear actuator materials will be prepared using this new electropositive shape effect.