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This study investigates the damping properties of Cu–Al–Mn shape memory alloys (SMAs) with various chemical compositions and the effects of the addition of quaternary alloying elements Ag and Nb on the microstructure, martensitic transformation behavior, and damping capacity of SMAs. Compared to other Cu–12Al– x Mn (x = 4–7 wt%) SMAs, Cu–12Al–5Mn has a more significant inherent and intrinsic internal friction (IF PT + IF I) peak above room temperature. The addition of Ag or Nb to Cu–12Al–5Mn reduced the grain size, thereby increasing the hardness of the alloys; however, the damping capacity and temperature of the IF PT + IF I peak decreased simultaneously. The addition of Ag to Cu–12Al–5Mn significantly reduced the damping capacity (IF PT +IF I peak) because of the notable decrease in the amount of transformed martensite. Moreover, the addition of Nb to Cu–12Al–5Mn caused the AlNb 3 phase to precipitate, limiting the mobility of the martensite variant interfaces and slightly decreasing the damping capacity (IF PT + IF I peak). Among the Ag- and Nb-doped Cu–12Al–5Mn SMAs, Cu–12Al–5Mn–1 Nb showed not only a significantly higher hardness but also a higher IF PT + IF I peak, with tan δ exceeding 0.01 at approximately 50 °C. [Display omitted] • In Cu-based SMAs, damping capacity depends on microstructure and the volume fraction of the transformed martensite. • Alloying elements with different mechanisms affect the damping performance of Cu-based SMAs. • In Cu-based SMAs, both damping capacity and mechanical strength improve by optimizing chemical composition. [ABSTRACT FROM AUTHOR]

• Annealing at different temperatures was used on cold rolling fe-13cr-4al-2mo thin-walled tubes. • The microstructure and axial tensile properties of the samples before and after annealing were measured. • The annealed samples were embrittled by aging, and the enhanced particles and hardness were characterized. • The strengthening mechanism of FeCrAl alloy at room temperature and failure mechanism at high temperature were investigated. FeCrAl alloy has great application potential to replace traditional zirconium alloy as an accident-tolerant fuel (ATF) candidate material. In this study, Fe-13Cr-4Al-2Mo-0.65Nb-0.4Ta alloy was prepared into a thin-walled tube with a diameter of 9.5 mm and a wall thickness of 0.35 mm by cold rolling. The effects of different annealing temperatures on the microstructure morphology, texture growth direction, and mechanical properties of FeCrAl alloy were studied., alloy underwent recovery and recrystallization with increasing annealing temperature, and the grain size increased. The theoretical calculation showed that the pinning action of Fe2Mo4C and Fe2Nb increased the dislocation density, and the interaction with the dislocation increased the room temperature strength. The addition of Ta led to the formation of more second-phase precipitates at the grain boundary, which hindered the growth and refined grains. The high-temperature stable second phase provided sufficient temperature strength for the alloy. [ABSTRACT FROM AUTHOR]