Research On Jet Electrochemical Turning Technology

In jet electrochemical turning,simple-shaped electrodes are used as the tool cathodes.The electrolyte flows out of the cathode by a positive flow method and sprays to the high-speed rotating workpiece through the machining gap.As the cathode is gradually fed,the workpiece anode undergoes an electrochemical dissolution reaction,forming the desired size of the part.The machining technology is mainly used for shafts,disks,sleeves and other rotating parts of difficult-to-machine materials,such as stainless steel and titanium alloy.The machining technology has the advantages of high machining efficiency,good surface quality,simple tool cathode manufacturing,and strong flexibility during machining.In this paper,the simulation analys is and experimental investigation on jet electrochemical turning of stainless steel 316L and titanium alloy T B6 materials are performed.The main research contents are as follows:（1）According to the principle of jet electrochemical turning,an experiment system device design scheme is proposed.The system consists of the machine tool body,power supply system,electrolyte system and motion control system.The original electrochemical milling-grinding equipment is transformed into a jet electrochemical turning experiment tool;For jet electrochemical turning of the cylindrical surface,a combined tool cathode and its positioning fixture are designed;The polar ization curve experiments are performed on stainless steel 316L and titanium alloy T B6 in 10 wt%Na NO₃ solution.The result show that the passivation-superpassivation phenomenon may exist in both materials in Na NO₃ solution.The superpassivation potentials are 1.7 V and 10.3 V,respectively.（2）The flow field s imulation is carried out on the electrolyte channel when the cylindr ical surfaces are machined by jet electrochemical turning,and the electrolyte discharge structure inside the tool cathode is improved according to the distribution characteristics of the flow field,obtaining four different design schemes;The electric field simulation of four cathode schemes for jet electrochemical turning is conducted,and the static current density distribution on the surface of the workpiece is calculated.The co MParison shows that scheme four is the optimal design scheme;Using cathode scheme four,the jet electrochemical turning experiments are carried out on the cylindr ical surface.According to the difference of machining efficiency and surface quality of the workpiece,the cathode scheme four is chosen as the best one,and the correctness of simulation is confirmed.（3）Using machining efficiency and surface quality as indicators,the effects of machining voltage,tool cathode feed rate,workpiece rotating speed and the electrolyte pressure on the c ylindrical surface of 316L and TB6 jet electrochemical turning are studied.The previous research experience is summarized,and the surfaces of typical rotating body samples are machined to realize the removal of1 mm margin in the radial direction of the cylindrical surface,the curved contour surface and the cone surface,which proves the application potential of the jet electrochemical turning technology.Among them,the cylindrical surface of 316L and TB6 are machined.The material removal rate are 391.1mg/min and 196.7 mg/min,respectively,and the surface roughness Ra are 0.077μm and 3.368μm,respectively.