Research On Electrochemical Machining Technology Of Micro Grooves On Spur Gear Tooth Surface

The gear with solid lubricating material embedded in micro grooves on gear tooth surface has better performance in severe lubrication conditions.It is difficult to process required micro grooves on involute surface of spur gear by traditional machining methods.Electrochemical machining with the mask is developed from electrochemical machining and photolithography technology.The major advantages of ECM with the mask are high removal rate in combination with the damage-free of workpiece surface.Thus,ECM with the mask is an effective method to process micro grooves on gear tooth surface.Based on the distribution characteristics of micro grooves on gear tooth surface,two kinds of shaped cathodes are designed,one with electrolyte flow slot and the other without.Each cathode can form two electrolyte flow modes respectively.The effects of four electrolyte flow modes on the stability of the machining gap flow field are analyzed using computational fluid dynamics.The results show that the cathode without electrolyte flow slot is conducive to electrolyte flow during ECM with the mask,notably when the electrolyte flows into the machining gap from face of the gear.Besides,the relationship between flow velocity and back pressure was studied.Based on the preferred cathode structure model and electrolyte flow mode,a fixture system for ECM with the mask micro grooves on gear tooth surface was designed,including gear positioning and clamping mechanism,electrolyte sealing device and cathode,etc.By calculating the load on workpiece in ECM,the selection of NC turntable and stepper motor was completed.The static analysis of load-bearing part was carried out using ANSYS.The results show that the structure design of spindle is reasonable.Based on the analysis of machining gap electric field characteristic of ECM with the mask,the electric field simulation model of single micro groove in ECM with the mask was established using COMSOL software.The forming process of micro-groove was simulated dynamically using corrosion module.The distribution of current density on the surface of workpiece was researched when the parameters changed such as processing gap,mask thickness mask groove width and processing voltage.The effect of each process parameter on the morphology of micro-groove was analyzed,and suitable process parameters was selected.