Abstract Electron beam melted Ti–48Al–2Cr–2Nb alloy has undesirable creep resistance due to a near-gamma structure that is not proper for creep. We aimed to control the microstructure of EBM-built Ti–48Al–2Cr–2Nb using two-step heat treatment to improve the high-temperature (750 °C) creep resistance while also maintaining room-temperature ductility. As a result of two-step heat treatment, heat-treated EBM-built Ti–48Al-2r-2Nb alloy has a nearly lamellar microstructure with a thin lamellar structure and fine equiaxed gamma grains. High-temperature creep resistance was significantly improved after two-step heat treatment by inducing a thin lamellar structure. Room temperature ductility was also maintained even while containing a lamellar structure.

中文翻译：

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两步热处理提高电子束熔化γTi-48Al-2Cr-2Nb合金的抗蠕变性

摘要 电子束熔化的 Ti-48Al-2Cr-2Nb 合金具有不适合蠕变的近伽马结构，因此具有不良的抗蠕变性。我们旨在使用两步热处理控制 EBM 制造的 Ti-48Al-2Cr-2Nb 的微观结构，以提高高温 (750 °C) 抗蠕变性，同时保持室温延展性。作为两步热处理的结果，热处理的 EBM 构建的 Ti-48Al-2r-2Nb 合金具有近乎层状的显微组织，具有薄层状结构和细小的等轴伽马晶粒。通过诱导薄层状结构，两步热处理后高温抗蠕变性显着提高。即使在含有层状结构的情况下也保持室温延展性。