The microstructure, martensitic transformation, and thermal cycling stability of Ni56Mn21Cu4Ga19 high-tem- perature shape memory ribbons subjected to different annealing conditions were investigated and compared with ...The microstructure, martensitic transformation, and thermal cycling stability of Ni56Mn21Cu4Ga19 high-tem- perature shape memory ribbons subjected to different annealing conditions were investigated and compared with that of the bulk master alloy. It was shown that 7 phases precipitated in the bulk and the ribbons annealed for 5 h at 800 and 900 ℃, which lead to the same poor thermal cycling stability. However, the formation of 7 phase was inhibited in the ribbons annealed at 700 ℃ for 30 rnin and 5 h, which remarkably improved the thermal cycling stability and also shifted the martensitic transformation to a lower temperature with a drop of about 60 ℃ than other three samples.展开更多
基金supported by the National Natural Science Foundation of China (No. 51101040)Harbin Special Fund for Innovation Talents of Science and Technology (No. 2013RFLXJ030)the State Scholarship Fund of China
文摘The microstructure, martensitic transformation, and thermal cycling stability of Ni56Mn21Cu4Ga19 high-tem- perature shape memory ribbons subjected to different annealing conditions were investigated and compared with that of the bulk master alloy. It was shown that 7 phases precipitated in the bulk and the ribbons annealed for 5 h at 800 and 900 ℃, which lead to the same poor thermal cycling stability. However, the formation of 7 phase was inhibited in the ribbons annealed at 700 ℃ for 30 rnin and 5 h, which remarkably improved the thermal cycling stability and also shifted the martensitic transformation to a lower temperature with a drop of about 60 ℃ than other three samples.
