将α+β两相区精锻, 直径为30和45 mm (分别定义为D30和D45)的Ti60棒材分别在950, 1000和1050 ℃进行固溶+时效热处理, 研究了热处理温度对棒材织构和拉伸性能的影响. 结果表明, D45棒材锻态组织中, 棒材轴向与α相的<0001>或 < 10 1 ? 0 > 方向平行的丝织构较强; 950 ℃热处理后显微组织和织构变化不明显. 随固溶温度升高, α相的<0001>丝织构增强, 而 <10 1 ? 0 > 丝织构密度减弱. 固溶温度对棒材强度的影响不大. D30棒材锻态组织中主要存在 < 10 1 ? 0 > 方向的丝织构; 随固溶温度升高, <0001>丝织构逐渐增强, 棒材的室温强度显著升高.

Microstructure and texture of titanium alloy are determined by thermomechanical and heat treatments and can significantly affect the mechanical properties of the final products. In this work, the microstructure and texture evolution during the heat treatment in α/β and β phase field in Ti60 precision forging bars were investigated. The results implied that the actual deformation temperature gradually decreased during precision forging processes. The microstructure and texture of Ti60 bar were determined by the finish forging temperature and the diameter, and strong microtexture macrozones existed in the forged Ti60 bar. For the bar with diameter of 45 mm (D45), the finish forging temperature fell in the lower temperature region of the α/β phase field, and the main α textures in these bars were <0001> and < 10 1 ? 0 > fiber texture components in initial Ti60 bar. The similarity of the microstructure and texture were found after heat treatment at 950 ℃. The intensity of < 10 1 ? 0 > fiber texture gradually decreased while that of <0001> fiber texture increased with the increase of the heat treatment temperature. Heat treatments have little influence on the strength of forged Ti60 bars of D45, while their ductility was reduced after β heat treatment. For the bar with diameter of 30 mm (D30), the finish forging temperature was below the α/β phase field, and the main α texture in those bars was < 10 1 ? 0 > fiber texture component. The intensity of <0001> fiber texture in those bars increased while that of < 10 1 ? 0 > fiber texture gradually decreased with the increase of the heat treatment temperature. Their room temperature strength significantly increased with the increase of the heat treatment temperature, and yield strength and tensile strength reached to 1086 and 1144 MPa, respectively, but the elongation only 3.3% after β heat treatment.