In this study, we investigated the early nucleation and growth of grain boundary α during the aging heat treatment of Ti-5553. Through a correlative approach using scanning electron microscopy, electron backscatter diffraction, transmission Kikuchi diffraction, transmission electron microscopy, and atom probe tomography, high-angle β-grain boundaries were investigated in detail to understand the evolution of the precipitation of grain boundary α through nucleation and subsequent growth. It is found that at grain boundaries there is a pronounced nucleation of α precipitates with similar orientations. Growth of these similarly orientated α precipitates, in the later stages, leads to their agglomeration and the formation of grain boundary α. This investigation provides insights into the formation of grain boundary α in its early stages of nucleation and growth.

中文翻译：

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亚稳β钛Ti-5Al-5Mo-5V-3Cr晶界α析出机制

在本研究中，我们研究了 Ti-5553 时效热处理过程中晶界 α 的早期形核和生长。通过使用扫描电子显微镜、电子背散射衍射、透射菊池衍射、透射电子显微镜和原子探针断层扫描的相关方法，详细研究了高角度β晶界，以了解晶界α通过成核析出的演化过程以及随后的增长。研究发现，在晶界处存在明显的具有相似取向的α析出物的形核。这些类似取向的 α 析出物的生长在后期导致它们团聚并形成晶界 α。这项研究提供了关于晶界 α 在成核和生长早期阶段的形成的见解。