分别在α+β两相区（925℃）、近β两相区（960℃）、准β单相区（995℃）对TC4-DT钛合金进行等温恒应变速率热拉伸变形，再进行920，940，960，980℃固溶和550，720℃时效热处理，研究了其流变应力的变化趋势和不同工艺处理后的显微组织。结果表明：在拉伸变形初期，流变应力迅速增大至峰值后缓慢减小，同时流变应力降幅随变形温度的升高而减小；拉伸变形温度越高或变形量越大，组织中初生α相量越少，针状α相越多，形成的片层组织越多；经960，995℃拉伸变形和不同温度固溶处理后，固溶温度越高，析出的针状α相越多，越易形成片层组织；经拉伸变形、固溶和时效处理后的显微组织和时效处理前的差别不大，但在针状α相间的β相上析出了次生α相，且时效温度越高，针状α相越粗大，片层组织越明显。

The isothermal constant strain rate hot tensile deformation was conducted on TC4-DT titanium alloy in α+β two-phase region (925℃), near-β two-phase region (960℃) and quasi-β single-phase region (995℃), respectively. And then solution at 950, 940, 960, 980℃ and aging at 550, 720℃ were carried out. The change trend of flow stress and microstructure after different treatment processes were studied. The results show that in the initial stage of tensile deformation, the flow stress increased rapidly to the peak value and then decreased slowly. The reduction extent of flow stress decreased with the increase of deformation temperature. The higher the tensile deformation temperature or the larger the deformation amount, the less the amount of primary α phase in the microstructure, and the more the needle-like α phase and the lamellar structure. The higher the solution temperature was, the more the needle-like α phase precipitated, and the easier the lamellar structure formed after tensile deformation of at 960, 995℃ and solution treatment at different temperatures. The microstructure after hot tensile deformation, solution and aging treatment had little difference from that before aging treatment, but the secondary α phase precipitated on β phases between needle-like α phases; the higher the aging temperature, the coarser the needle-like α phase, and the more obvious the lamellar structure.