Superelasticity associated with the martensitic transformation has found a broad range of engineering applications^1,2. However, the intrinsic hysteresis³ and temperature sensitivity⁴ of the first-order phase transformation significantly hinder the usage of smart metallic components in many critical areas. Here, we report a large superelasticity up to 15.2% strain in [001]-oriented NiCoFeGa single crystals, exhibiting non-hysteretic mechanical responses, a small temperature dependence and high-energy-storage capability and cyclic stability over a wide temperature and composition range. In situ synchrotron X-ray diffraction measurements show that the superelasticity is correlated with a stress-induced continuous variation of lattice parameter accompanied by structural fluctuation. Neutron diffraction and electron microscopy observations reveal an unprecedented microstructure consisting of atomic-level entanglement of ordered and disordered crystal structures, which can be manipulated to tune the superelasticity. The discovery of the large elasticity related to the entangled structure paves the way for exploiting elastic strain engineering and development of related functional materials.

与马氏体相变相关的超弹性已发现^1,2，广泛的工程应用。但是，固有磁滞³和温度灵敏度⁴一阶相变的存在严重阻碍了智能金属组件在许多关键领域的使用。在这里，我们报道了[001]取向NiCoFeGa单晶具有高达15.2％应变的大超弹性，表现出无滞后的机械响应，较小的温度依赖性和高储能能力以及在宽温度和组成范围内的循环稳定性。原位同步加速器X射线衍射测量表明，超弹性与应力引起的晶格参数连续变化以及结构波动有关。中子衍射和电子显微镜观察显示出前所未有的微观结构，包括有序和无序晶体结构的原子级缠结，可以对其进行调节以调节超弹性。