Machining micro-holes with high-power pulsed laser is very common, but due to the mechanism of laser processing, micro-cracks, recast layer and heat-affected zones in hole walls are difficult to avoid. Hybrid processing of laser beam machining with Electrochemical Machining (ECM) can effectively eliminate these defects and improve processing efficiency. This paper proposes to use a synchronized laser and electrochemical machining method. A metal tube electrode is used to guide and transmit the laser to the machining area to achieve high coaxial coupling of laser and electrochemical energy. An experimental system of laser beam machining with ECM is developed, and the surface quality of hole walls are studied on aluminum alloy and stainless-steel workpiece. The effects of ECM voltage and current on the rate of laser beam machining with ECM and the surface quality of hole walls (recast layer, micro-cracks, surface roughness, etc.) are analyzed. The experimental results show that the machining current increases with the increase of pulse voltage, the material removal rate increases, the micropore clearance increases, and the machining precision decreases. By adopting appropriate ECM parameters, the fast processing of micro-holes is realized, with smooth side wall, small taper, good entrance roundness, and the recast layer of the hole wall is fully removed.
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