Ni-Ti 基形状记忆合金相变行为与弹热效应:从马氏体相变、应变玻璃转变到性能调控

Elastocaloric cooling technology，which relies on the crystal structural phase transformation of Ni-Ti-based shape memory alloys，offers advantages such as high efficiency，energy saving，and environmental friendliness. These advantages establish it as a promising alternative to conventional vapor-compression refrigeration. Large adiabatic temperature changes，high material coefficient of performance，excellent fatigue resistance，and a wide operating temperature window are critical indicators of elastocaloric performance，attaining all of these simultaneously remains challenging. This bottleneck has constrained the practical development of the technology. This review systematically introduces the intrinsic relationships and research progress among the manufacturing processes，microstructures，phase transformations，and elastocaloric properties of Ni-Ti-based shape memory alloys. Firstly，it compares conventional and additive manufacturing processes，analyzing their effects on material microstructures and performance. Secondly，from the perspective of substructural features such as grain morphology，precipitates，and twins，it discusses the mechanism by which the microstructure regulates both the thermoelastic martensitic transformation and the defect-induced strain glass transition. Subsequently，the review elaborates on the primary controlling parameters of the elastocaloric effect across different phase transformation pathways，and summarizes technical approaches to enhance overall cooling performance. Finally，this review outlines future research directions：coordinating thermoelastic martensitic transformation and strain glass transition through process innovation and novel alloy design to achieve synergistic optimization of elastocaloric properties；and combining structural design to further enhance heat transfer efficiency，reduce driving energy consumption，and improve adaptability to operating conditions.