Abstract The solidification process of Ti45Al2Nb2Ta0.8B (B4522Ta) and Ti45Al2Nb2Hf0.8B (B4522Hf) Bridgman samples were studied through directional solidification. Boron addition at 0.8 at. % was found to have changed the orientation relationship of peritectic α with β dendrites. The peritectic alpha is randomly oriented in both B4522Ta and B4522Hf, it was likely to be inoculated by boride precipitates at the β/liquid interfaces during peritectic transformation. The alloying effect of Ta and Hf on the peritectic reaction was similar. Borides precipitated earlier in Ta-containing alloy than that in Hf-containing alloy during solidification.

中文翻译：

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合金对 Ti45Al2Nb2Ta0.8B 和 Ti45Al2Nb2Hf0.8B 凝固行为和晶粒细化的影响

摘要 通过定向凝固研究了Ti45Al2Nb2Ta0.8B (B4522Ta)和Ti45Al2Nb2Hf0.8B (B4522Hf) Bridgman试样的凝固过程。硼添加量为 0.8 at。% 被发现改变了包晶 α 与 β 枝晶的取向关系。包晶 α 在 B4522Ta 和 B4522Hf 中随机取向，很可能在包晶转变过程中被 β/液体界面处的硼化物沉淀接种。Ta和Hf对包晶反应的合金化作用相似。在凝固过程中，硼化物在含 Ta 合金中比在含 Hf 合金中沉淀得更早。