The microstructure, martensitic transformation, and thermal cycling stability of Ni56Mn21Cu4Ga19high-temperature shape memory ribbons subjected to different annealing conditions were investigated and compared with that of the bulk master alloy. It was shown that c phases precipitated in the bulk and the ribbons annealed for 5 h at 800 and 900 °C,which lead to the same poor thermal cycling stability. However, the formation of c phase was inhibited in the ribbons annealed at 700 °C for 30 min 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 °C than other three samples.
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