Smart actuators, using materials with a memory, are an attractive alternative to conventional actuators due to their unique properties, such as high energy density, low power-to-weight ratio, simplicity of design, and miniaturization of size. However, the continuous cyclic operation of such devices, within their transformation temperature range, leads to the degradation of their functional properties. In this paper, the degradation of functional properties, such as recovery strain, permanent strain, and critical transition temperatures, of an Ni₄₅Ti₅₀Cu₅ (at.%) shape memory alloy, aged at four different temperatures, ranging from 450 to 600 °C, was experimentally investigated under constant stress. The results reveal that all alloys underwent a single-step transition from B2 → B19’ at all aging temperatures. The aging temperature has a significant impact on recovery strain and permanent strain. The permanent strain accumulation after every cycle is minimized as the temperature of aging is raised to 550 °C due to the strengthening of the matrix by precipitate particles. Above this temperature, it starts to increase due to the coarsening of the precipitate particles. Aging treatment also helps to achieve faster cyclic stability during thermomechanical cycling.

使用具有存储器的材料的智能执行器由于其独特的特性（例如高能量密度，低功率重量比，设计简单和尺寸小型化）而成为常规执行器的有吸引力的替代方案。然而，这种装置在其转变温度范围内的连续循环操作导致其功能特性的降低。在本文中，Ni ₄₅ Ti ₅₀ Cu ₅的功能特性退化，例如恢复应变，永久应变和临界转变温度（at。％）形状记忆合金，在恒定应力下，在450至600°C的四个不同温度下进行了时效研究。结果表明，所有合金在所有时效温度下都经历了从B2→B19'的单步转变。时效温度对恢复应变和永久应变具有重大影响。由于析出物颗粒对基体的强化，随着时效温度升高至550°C，每个循环后的永久应变积累得以最小化。在此温度以上，由于沉淀颗粒的粗化而开始增加。老化处理还有助于在热机械循环中实现更快的循环稳定性。