钛合金前缘加强边是大型复材叶片的关键部件，其结构为复杂薄壁V型长槽，具有深窄、弱刚性特征。该零件的内腔和外型需通过多轴精密加工成形，然而加工过程在其内腔和外型引入的残余应力分布不平衡，会诱发明显的弯扭复合变形，导致零件轮廓度等关键尺寸超差。因此，提出一种基于外型加工刀轴矢量优化的加强边残余应力变形控制方法。该方法通过优化外型多轴加工的刀轴矢量，主动调控外型的加工残余应力分布，使其与内腔的残余应力分布相互平衡，从而实现对弯扭变形的精准控制。首先，采用双曲正切函数描述TC4钛合金多轴加工的残余应力梯度分布规律；然后，在Abaqus软件平台上，采用薄壳应力贴合方法将残余应力作为载荷施加，建立了加强边残余应力变形的有限元仿真模型；基于该模型，建立了刀轴侧倾角与关键位置变形量之间的量化映射关系，并完成了外型加工刀轴矢量的优化；最后，通过多组零件的加工实验验证了该方法的有效性。实验结果表明，优化后的零件轮廓度误差平均降低了23.41%。该方法为钛合金前缘加强边的高精度多轴加工提供了可靠的技术方案，对提升复材叶片的制造质量与服役可靠性具有直接的工程意义。

The titanium alloy leading edge protection cap is a critical component of large composite blades， characterized by a complex thin-walled V-shaped long slot structure with deep， narrow， and low-stiffness features. Both its inner cavity and outer profile require shaping through multi-axis precision machining. However， the unbalanced distribution of residual stress introduced by the machining process between the inner cavity and outer profile can induce significant bending-torsion coupling deformation， leading to out-of-tolerance deviations in key dimensions such as the contour accuracy. Therefore， a residual stress deformation control method for the protection cap is proposed based on the optimization of the cutter axis vector in machining outer profile. By optimizing the cutter axis vector in multi-axis machining， this method actively regulates the residual stress distribution on the outer profile， balancing it with that in the inner cavity to achieve precise control of the bending-torsion deformation. Firstly， the hyperbolic tangent function is employed to characterize the residual stress gradient distribution induced by multi-axis machining of TC4 titanium alloy. Subsequently， a finite element simulation model for the residual stress-induced deformation of the protection cap is established on the Abaqus software platform， where the residual stress is applied as loads using the thin-shell stress-fitting method. Based on this model， a quantitative mapping relationship between the cutter tilt angle and the deformation at key locations is established， thereby completing the optimization of the cutter axis vector for outer profile machining. Finally， the effectiveness of the proposed method is validated through machining experiments on multiple parts. Experimental results show that the contour error of the optimized parts is reduced by an average of 23.41%. This method provides a reliable technical solution for the high-precision multi-axis machining of titanium alloy leading edge protection caps， holding direct engineering significance for enhancing the manufacturing quality and service reliability of composite blades.