Abstract In this study, the martensitic transformation and superelastic behaviors were investigated in (Ni0.35Ti0.30Cu0.15Zr0.20)100-xSix (x = 0, 0.25, 0.5, and 1.0) alloys. After homogenization treatment, the microstructure consists of a B2 austenite matrix and a small fraction of secondary solidification particles at the grain boundaries. The concentration of Si in the B2 matrix increases with increasing Si content. The martensitic transformation temperature drops significantly as the Si content increases, i.e., an approximately 200 K decrease with the addition of 1.0 at% Si. The stress for inducing the martensitic transformation significantly increases with the increase in Si, whereas the strain to the final fracture decreases. After the cyclic loading test, the normalized stress for inducing the martensitic transformation increases with the addition of Si, whereas the residual plastic strain decreases. Thus, the Ni–Ti–Cu–Zr alloy with a minor addition of Si shows high potential for structural applications, owing to a good combination of strength and superelastic properties.

中文翻译：

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通过在 Ni-Ti-Cu-Zr 合金中添加 Si 提高强度和超弹性循环耐久性

摘要 在这项研究中，研究了 (Ni0.35Ti0.30Cu0.15Zr0.20)100-xSix (x = 0、0.25、0.5 和 1.0) 合金的马氏体转变和超弹性行为。均质化处理后，显微组织由 B2 奥氏体基体和小部分晶界处的二次凝固颗粒组成。B2基体中Si的浓度随着Si含量的增加而增加。随着Si含量的增加，马氏体转变温度显着下降，即，随着添加1.0 at% Si，降低约200 K。诱导马氏体转变的应力随着 Si 的增加而显着增加，而最终断裂的应变减小。循环加载试验后，诱导马氏体转变的归一化应力随着 Si 的加入而增加，而残余塑性应变减少。因此，由于强度和超弹性性能的良好结合，添加少量 Si 的 Ni-Ti-Cu-Zr 合金在结构应用方面具有很高的潜力。