Microstructure and hot flow stress at 970℃ of various heat-treated Ti2AlNb sheets

作者：Yong Wu^*; Rong-Lei Fan; Xian-Jun Zhou; Ming-He Chen

来源：Rare Metals, 2020, 39(06): 695-706.

The microstructure and hot tensile behaviors of the different heat-treated Ti2AlNb sheets were investigated by backscattered electron image (BSE),electron backscattering diffraction (EBSD),transmission electron microscope (TEM) and tensile tests.The grain sizes and contents ofα2,B2/βand O phases were quantitatively studied.As the heating time increases at 970℃,the mean grain size and content ofα2-phase increased.The grain shapes and distributions of the O-phase lamellar grains were affected by the heat treatments.The plastic deformation promoted the O→B2/βphase transition and the globularization of O-phase lamellar grains at 970℃.Calculated by the creep equation and the iso-stress method,the grain size exponent wasμ=1.1 and the relationship between the material constants of B2/βand O phase was KO=1.14KB2/β.

• 单位
  南京航空航天大学