The NiTiHf-Nb alloy exhibits good workability as well as high-temperature shape memory property. In this work, effects of cooling rate on martensitic transformation behavior and shape memory property for Ni-rich (Ni_50.1Ti_34.9Hf₁₅)₈₅Nb₁₅ alloy were investigated. For comparison, the martensitic transformation behavior and shape memory property of Ni_50.1Ti_34.9Hf₁₅ alloy were also investigated. As the cooling rate decreased from water cooling to furnace cooling after solution treatment, the martensitic transformation temperatures (TTs) of (Ni_50.1Ti_34.9Hf₁₅)₈₅Nb₁₅ alloy decreased gradually, whereas the decrease was not obvious for Ni_50.1Ti_34.9Hf₁₅ alloy. The increased valence electron concentration (c_v) should account for the decrease in TTs of (Ni_50.1Ti_34.9Hf₁₅)₈₅Nb₁₅ alloy. The shape memory effect strain increased with the decrease in the cooling rate for both two alloys, and the largest shape memory effect strain of 2.6% can be obtained in furnace-cooled (Ni_50.1Ti_34.9Hf₁₅)₈₅Nb₁₅ alloy. This enhancement in the shape memory property should be ascribed to the precipitation of H-phase in furnace-cooled (Ni_50.1Ti_34.9Hf₁₅)₈₅Nb₁₅ alloy.

NiTiHf-Nb 合金具有良好的可加工性和高温形状记忆性能。在这项工作中，研究了冷却速度对富镍 (Ni _50.1 Ti _34.9 Hf ₁₅ ) ₈₅ Nb ₁₅合金马氏体转变行为和形状记忆性能的影响。为了比较，还研究了 Ni _50.1 Ti _34.9 Hf ₁₅合金的马氏体转变行为和形状记忆性能。随着固溶处理后从水冷到炉冷的冷却速度降低，(Ni _50.1 Ti _34.9 Hf ₁₅ )的马氏体转变温度(TTs )₈₅ Nb ₁₅合金逐渐下降，而Ni _50.1 Ti _34.9 Hf ₁₅合金下降不明显。增加的价电子浓度 (c _v ) 应说明 (Ni _50.1 Ti _34.9 Hf ₁₅ ) ₈₅ Nb ₁₅合金的TT 降低。两种合金的形状记忆效应应变随着冷却速度的降低而增加，在炉冷(Ni _50.1 Ti _34.9 Hf ₁₅ ) ₈₅ Nb _{15 中}可以获得2.6%的最大形状记忆效应应变合金。这种形状记忆性能的增强应归因于炉冷 (Ni _50.1 Ti _34.9 Hf ₁₅ ) ₈₅ Nb ₁₅合金中 H 相的析出。