Method for improving removal efficiency and surface roughness in laser-electrolytic hybrid processing of TC4 titanium alloy

TC4 titanium alloys are increasingly utilized in industrial applications due to their excellent mechanical and physical properties. Laser–electrolytic hybrid machining, as an advanced multi-energy-field manufacturing technology, represents a promising approach for enhancing the machining efficiency of TC4 titanium alloys. However, the formation of oxide layers during hybrid processing degrades the surface quality. Therefore, this study proposes a laser–electrolytic hybrid machining method incorporating a tool electrode with an adjustable tilt angle. By adjusting the tilt angle of the tool electrode, the evacuation of machining products from the machining gap and the distribution of current density are optimized, thereby improving both the material removal rate (MRR) and surface roughness. Forward and reverse machining experiments were conducted under different tilt angles. The results indicate that, compared with vertical machining, inclined machining achieves a maximum increase of 112% in MRR. Surface composition analyses reveal that reverse-inclined machining reduces the oxygen content on the machined surface, thereby mitigating oxidation effects. Furthermore, this approach achieves a maximum reduction of 29% in surface roughness. Overall, the proposed approach enhances the flexibility and performance of laser–electrolytic hybrid machining and demonstrates its feasibility for high-quality and high-efficiency processing of TC4 titanium alloys.