TA15钛合金热剪旋件的几何精度与显微组织分析(英文)

为了揭示偏离率和加热温度对TA15钛合金加热剪切旋压件的影响机制,研究了不同偏离率下热剪旋件的几何精度和微观组织。结果表明:在负偏离下工件会发生径缩,且温度的突然降低会使径缩更严重。在正偏离条件下且加热温度缓慢降低时,沿工件底部到口部有明显扩径。沿热剪旋工件厚向的不均匀变形使工件晶粒细化且近外层晶粒比近内层晶粒细小。在近外层可能形成纤维组织,该纤维组织的扭曲程度随着偏离率的减小而增加。近零偏离和保持加热温度在合理范围时有利于获得几何精度高和微观组织均匀的工件。

Geometric precision and microstructure evolution of TA15 alloy by hot shear spinning

To investigate the mechanistic influence of the deviation ratio and heating temperature on the hot shear spinning of TA15 alloy, the geometric precision and microstructure evolution of the hot-spun parts were experimentally investigated under different conditions. The results show that diametrical shrinkage occurs under a negative deviation ratio, and a sudden decrease in heating temperature creates a sharp increase in the shrinkage. A pronounced diametrical enlargement increases from the bottom location to the open end of the workpiece under a positive deviation ratio with a gradual decrease in heating temperature. The hot shear spinning process can lead to a non-uniform microstructure that results from the non-uniform deformation along the thickness direction. The distortion degree of the fiber microstructure formed near the outer surface increases with the decrease in the deviation ratio. A deviation ratio near zero and heating to a temperature within the desired range are beneficial conditions for obtaining spun parts with satisfactory geometric precision and a uniform microstructure.