Abstract Joining of Ti2AlNb alloy to TiAl intermetallics was conducted by the newly-developed Ti–Ni–Nb–Zr brazing filler alloy. The microstructure evolution of the joints was investigated by scanning electron microscope (SEM), energy dispersive spectrometer (EDS) and electron backscatter diffraction (EBSD). The macro-micro mechanical properties were studied by shear test and nano-indentation test. Typical interfacial microstructures across the brazing seam were Ti2AlNb substrate, α2-Ti3Al+β-Ti, γ-TiAl+Ti2Ni+TiNi+α2-Ti3Al, α2-Ti3Al+β-Ti, TiAl substrate. The Ti2Ni phase were firstly dissolved in the joints brazed at 1000 °C for 10 min and then precipitated after a prolonged holding time of 15 min. The nano-indentation test revealed that Ti2Ni phase exhibited the highest hardness of 12.60 GPa. The joints brazed at 1000 °C/15 min presented the maximum shear strength of 271 MPa. The dissolution and precipitation behavior of Ti2Ni phase was also discussed.

中文翻译：

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使用新开发的 Ti-Ni-Nb-Zr 钎料的 Ti2AlNb/TiAl 钎焊接头的组织演变和力学性能

摘要 Ti2AlNb 合金与 TiAl 金属间化合物的接合是通过新开发的 Ti-Ni-Nb-Zr 钎料合金进行的。通过扫描电子显微镜（SEM）、能谱仪（EDS）和电子背散射衍射（EBSD）研究了接头的微观结构演变。通过剪切试验和纳米压痕试验研究了宏观-微观力学性能。横跨钎焊缝的典型界面显微组织是 Ti2AlNb 基体、α2-Ti3Al+β-Ti、γ-TiAl+Ti2Ni+TiNi+α2-Ti3Al、α2-Ti3Al+β-Ti、TiAl 基体。Ti2Ni 相首先溶解在在 1000°C 下钎焊 10 分钟的接头中，然后在 15 分钟的延长保温时间后析出。纳米压痕测试表明，Ti2Ni 相的硬度最高，为 12.60 GPa。在 1000 °C/15 min 下钎焊的接头的最大剪切强度为 271 MPa。还讨论了 Ti2Ni 相的溶解和析出行为。