Ultra-high temperature aging was conducted on the Cu-11.9Al-2.5Mn (wt.%) shape memory alloy (SMA) with the aim of damping improvement. The martensite laths were refined, and the controllable precipitation of γ phase was realized. As the aging temperature decreased or the aging time prolonged, the amount of γ particles increased. The damping of the Cu–Al–Mn SMA measured in this study belongs to non-linear damping, and the damping plateau in the martensite state mainly arises from the sliding of the martensite/martensite interfaces and the stacking faults in martensitic variants. The increased density of the martensite/martensite interfaces caused by grain refinement, the de-pinning of dislocations, and the annihilation of quenched-in vacancies after aging contributed to the increase of damping, whereas the increased density of stacking faults and the pining of γ particles on various interfaces leaded to the decrease of damping. The specimen aged at 590 °C for 5 min has the highest damping plateau. Its damping capacity at room temperature is 3.5 times that of the quenched specimen. The effect of aging on the tensile properties was also studied, and based on in-depth microstructural observation, correlated mechanisms were discussed.

中文翻译：

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通过超高温时效获得Cu-Al-Mn形状记忆合金的优异阻尼性能

对 Cu-11.9Al-2.5Mn (wt.%) 形状记忆合金 (SMA) 进行超高温时效，以改善阻尼。马氏体板条细化，实现了γ相的可控析出。随着时效温度降低或时效时间延长，γ粒子数量增加。本研究中测得的Cu-Al-Mn SMA的阻尼属于非线性阻尼，马氏体状态下的阻尼平台主要源于马氏体/马氏体界面的滑动和马氏体变体中的堆垛层错。晶粒细化、位错脱钉以及时效后淬火空位的消除导致马氏体/马氏体界面密度的增加有助于阻尼的增加，而堆垛层错密度的增加和γ的钉扎各个界面上的颗粒导致阻尼降低。在 590 °C 老化 5 分钟的样品具有最高的阻尼平台。其室温阻尼能力是淬火试样的3.5倍。还研究了时效对拉伸性能的影响，并基于深入的微观结构观察，讨论了相关机制。