Zhou Haitao, Kong Fantao, Wang Yanbo, Hou Xiangwu, Cui Ning, Sun Jingli
Research & Development Center, Shanghai Spaceflight Precision Machinery Institute, Shanghai 201600, China.
School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China.
Materials (Basel). 2021 Aug 25;14(17):4817. doi: 10.3390/ma14174817.
In this paper, the deformation and phase transformation of disordered α phase in the (α + γ) two-phase region in as-forged Ti-44Al-8Nb-(W, B, Y) alloy were investigated by hot-compression and hot-packed rolling. The detailed microstructural evolution demonstrated that the deformed microstructure was significantly affected by the deformation conditions, and the microstructure differences were mainly due to the use of a lower temperature and strain rate. Finer α grains were formed by the continuous dynamic recrystallization of α lamellae and α grains distributed around lamellar colonies. Moreover, the grooved γ grains formed by the phase transformation from α lamellae during hot rolling cooperated with and decomposed α lamellae. A microstructure evolution model was built for the TiAl alloy at 1250 °C during hot rolling.
本文通过热压缩和热包套轧制研究了锻造态Ti-44Al-8Nb-(W,B,Y)合金在(α+γ)两相区无序α相的变形与相变。详细的微观组织演变表明，变形微观组织受变形条件的显著影响，微观组织差异主要源于较低的温度和应变速率。α片层的连续动态再结晶以及分布在片层团簇周围的α晶粒形成了更细小的α晶粒。此外，热轧过程中由α片层相变形成的沟槽状γ晶粒与α片层协同作用并使其分解。建立了TiAl合金在1250℃热轧过程中的微观组织演变模型。
