Research Advances and Practical Applications of Cu-Al-Mn Shape Memory Alloys

Cu-Al-Mn shape memory alloys (SMAs), as a new generation of low-temperature responsive functional materials, exhibit excellent shape memory effect, super-elasticity, high damping capacity, and good workability. These properties make them highly promising for applications in aerospace, civil engineering, mechanical electronics, and biomedical fields. This review systematically summarizes the fundamental principles and key characteristics of Cu-Al-Mn SMAs, including thermoelastic martensitic transformation mechanisms, super-elastic behavior, damping properties, and phase diagram structures. In terms of alloy design, researchers have optimized transformation temperatures, recovery strain, and thermal stability by adjusting the Al/Mn ratio and introducing trace elements, such as Ti, V, and Zr. In manufacturing, advanced processes such as laser powder bed fusion, powder metallurgy, and rapid solidification significantly improve microstructural uniformity and performance stability. The paper further discusses microstructural control, multi-physical field coupling effects (magnetocaloric and elastocaloric effects), and fatigue life enhancement strategies. Through bibliometric and visualization analysis, current research hotspots and trends are also highlighted. Despite the great potential of Cu-Al-Mn SMAs in low-temperature functional applications, challenges remain in understanding the reverse martensitic transformation mechanism, improving cyclic stability, and adapting to extreme service environments. Future research can focus on integrating multiscale simulations, additive manufacturing, and multifunctional material design to accelerate the engineering application of Cu-Al-Mn SMAs in structural health monitoring, intelligent actuation, and energy conversion.