Effect of machining voltage on microstructure depth and taper in laser-assisted electrochemical machining

To investigate the effect of machining voltage on the microstructural depth and taper in laser-assisted electrochemical machining, a multi-physics coupled simulation model integrating electric, flow and thermal fields was established. The evolution of temperature, gas volume fraction and current density within the machining gap was analysed, and their effects on microstructure depth and taper were investigated experimentally. The results indicate that increasing the machining voltage enhances the inter-electrode electric field strength, leading to an increase in current density while promoting cathodic hydrogen evolution and Joule heat generation. Consequently, the gas volume fraction and temperature in the machining zone increase simultaneously, with the middle position exhibiting the highest rise and peak due to current density concentration. As the voltage increases from 8 V to 14 V, the micro-structure depth increases from 98.75 μm to 114 μm, while the taper increases from 10.48° to 18.28°. At lower voltages, stray corrosion is relatively weak, resulting in better microstructure forming accuracy and surface quality. Higher voltages enhance material removal rate and increase machining depth, but the non-uniformity of the electric field and intensified bubble disturbance lead to increased taper. This study provides a theoretical basis and technical support for the precise regulation of machining voltage in laser-assisted electrochemical machining microstructure.