Abstract

This research is aimed at Laser processing of micro holes there are recast layer and microcracks, analyzed the laser processing of recast layer formation mechanism and surface geometry features not, and for the laser processing of the formation of the recast layer in the process of analog simulation, for electrochemical finishing processing to remove the recast layer to provide a theoretical basis. The laser-electrolysis asynchronous composite processing experimental system was developed, and the electrolytic removal of recast layer on the wall of laser perforated holes and the process research of aperture trimming were carried out, which mainly analyzed the effects of electrolysis voltage, electrolyte and pulse electrolysis parameters on the rate of electrolysis and the effect of the removal of the recast layer. The cathode lifting method is also proposed to lift the tool cathode for orifice shaping after effective removal of the recast layer. The experimental results show that: when the current density is greater than 10.09 A/cm2, the electrolysis rate is proportional to the voltage; when the constant voltage electrolysis, the mixed solution of NaNO3 and NaCl enhances the effect of the recast layer removal significantly, and relative to the single solution with the same electrical conductivity, the value of the change in the surface roughness of the workpiece before and after the finishing process is enhanced more significantly, and there is no significant difference in the processing efficiency; the low-frequency wide pulse and high-frequency narrow pulse in the pulse electrolysis processing is favorable for the removal of recast layer. Pulse, high-frequency narrow pulse is conducive to the improvement of electrolysis rate, and the frequency of 1 kHz, the duty cycle of 40% to 60% of the electrolysis rate is the largest; at the same time, the use of cathodic enhancement method of aperture trimming processing, the use of the truncation effect, through the appropriate electrolytic processing parameters, to achieve the complete removal of the laser hole hole wall recast layer at the same time to complete the aperture trimming processing, to meet the demand for the use of performance of the small holes to further enhance the processing efficiency and small holes, and to improve the processing efficiency of the laser hole. Enhance the processing efficiency and functionality of small holes.