Abstract The effect of Gd on the formation of a lamellar structure during ageing of quenched γ-TiAl based alloys was studied. Ti-47.1Al-1.8Nb-0.5Zr-0.3V-0.001Gd (0.001Gd) and Ti-46.9Al-1.6Nb-0.5Zr-0.5V-0.03Gd (0.03Gd) alloys were quenched from the alpha-phase field and aged at 400–800 °C. After quenching, a small amount of Gd2TiO5 particles was found in both alloys. Grain boundary segregation of Gd in the 0.03Gd alloy quenched from the alpha-phase field was detected. The α2→γ transformation kinetics with the formation of γ lamellae was found to be noticeably faster in the 0.001Gd alloy. In addition, an increase in the Gd percentage led to a reduction of the interlamellar spacing for all ageing conditions. The effect of Gd on surface energy and diffusion rate are discussed.

中文翻译：

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Gd添加对γ-TiAl基合金α2→γ相变动力学的影响

摘要 研究了Gd对淬火γ-TiAl基合金时效过程中层状组织形成的影响。Ti-47.1Al-1.8Nb-0.5Zr-0.3V-0.001Gd（0.001Gd）和Ti-46.9Al-1.6Nb-0.5Zr-0.5V-0.03Gd（0.03Gd）合金从α相场淬火并在 400–800 °C 下老化。淬火后，在两种合金中都发现了少量的 Gd2TiO5 颗粒。检测到从 α 相场淬火的 0.03Gd 合金中 Gd 的晶界偏析。发现在 0.001Gd 合金中随着 γ 片晶形成的 α2→γ 转变动力学明显更快。此外，Gd 百分比的增加导致所有老化条件下层间距的减小。讨论了 Gd 对表面能和扩散速率的影响。