超塑性成形是一种用于生产难变形钛基复合材料（TMC）的复杂形状部件的有前途的技术。对不同压下量的热轧TiB/近αTi基复合材料进行超塑性拉伸试验，研究基体微观结构特征和晶须取向对超塑性变形行为的影响。结果表明，与初始 T 型织构的复合材料相比，初始 BT 型织构和更细基体晶粒的复合材料在压下率为 80% 时表现出更低的流变应力和更大的伸长率，并且在压下率为 40% 时具有更好的延伸率。前者达到了 682%。变形过程中基体合金出现明显的晶体取向随机化和动态晶粒生长现象。在超塑性拉伸变形过程中，原本错位的 TiB 晶须逐渐向拉伸方向旋转，同时绕 [010] 轴圆周旋转，这将适应基体变形并分担更多从基体传递的载荷。TiB晶须的另一个重要调节机制是通过粒子刺激成核加速周围基体的动态再结晶。TEM 和 EBSD 观察以及 GND 分布分析证实，TiB/Ti 复合材料的主要超塑性变形机制是位错滑移和动态再结晶调节的晶/相边界滑动。这将适应基体变形并分担更多从基体传递的载荷。TiB晶须的另一个重要调节机制是通过粒子刺激成核加速周围基体的动态再结晶。TEM 和 EBSD 观察以及 GND 分布分析证实，TiB/Ti 复合材料的主要超塑性变形机制是位错滑移和动态再结晶调节的晶/相边界滑动。这将适应基体变形并分担更多从基体传递的载荷。TiB晶须的另一个重要调节机制是通过粒子刺激成核加速周围基体的动态再结晶。TEM 和 EBSD 观察以及 GND 分布分析证实，TiB/Ti 复合材料的主要超塑性变形机制是位错滑移和动态再结晶调节的晶/相边界滑动。

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Superplastic forming is a promising technique for producing complex-shaped components of hard-to-deform titanium matrix composites (TMCs). Superplastic tensile tests were performed on hot-rolled TiB/near-α Ti matrix composites with different reductions to investigate the effects of matrix microstructural characteristics and whisker orientation on superplastic deformation behavior. The results showed that the composite with initial BT-type texture and finer matrix grains at a rolling reduction of 80% exhibited lower flow stress and larger elongation than the composite with initial T-type texture at a rolling reduction of 40%, and superior elongation of 682% was achieved in the former. Significant randomization of crystal orientation and dynamic grain growth phenomenon occurred in the matrix alloys during deformation. The originally misaligned TiB whiskers gradually rotated to the tensile direction and simultaneously rotated circularly around the [010] axis during superplastic tensile deformation, which would accommodate the matrix deformation and share more load transferred from the matrix. Another important accommodation mechanism of TiB whiskers was to accelerate the dynamic recrystallization of the surrounding matrix by particle-stimulated nucleation. TEM and EBSD observations together with GND-distribution analysis confirmed that the primary superplastic deformation mechanism of TiB/Ti composites is grain/phase boundary sliding accommodated by dislocation slip and dynamic recrystallization.