Multi-Physical Fields Simulation And Experimental Study On Micro Electrochemical Drilling And Milling With Ultra Shout Pulse Valtage

With the rapid development of microelectronics technology and the increasing demand for microdevices,micro electrochemical machining have been widely used in aerospace,precision instruments,biomedical and other fields.However,at present,the stray corrosion phenomenon is serious and the machining localization is poor in electrochemical machining.For this reason,combining the basic theory of ultra short pulse and the machining principle of high-speed spiral electrode,this paper proposes a micro electrochemical drilling and milling process under the combination of ultra short pulse voltage and high-speed spiral micro electrode,the gap electric field and the gap flow field in the micro electrochemical machining were simulated,and a series of experimental studies were conducted.The main research content of this paper is as follows:The basic principle and characteristics of micro electrochemical machining with ultra short pulse voltage were analyzed.It was found that ultra short pulse voltage can be used for electrochemical machining,which can inhibit stray corrosion better and improve machining localization significantly,the electrochemical and flow field characteristics of electrochemical machining were analyzed.The analysis results provide theoretical guidance for subsequent simulation studies.This paper proposed a micro electrochemical drilling and milling process,combining ultra short pulse voltage and high-speed spiral micro electrode,and the simulation method and test device were introduced.The mathematical model of ultra short pulse gap electric field and the gap flow field were established,the reason why the high-speed spiral electrode promoted the renewal of the electrolyte was discussed,the micro electrochemical machining test platform was set up.The gap electric field and gap flow field in micro electrochemical drilling were simulated,and a series of micro electrochemical drilling experiments were completed.The integrated effects of electric field,electrochemical polarization and concentration polarization on electrochemical machining process were considered in turn,the current density of the machining gap and the shape change of the anode workpiece surface were simulated and predicted.When the factors considered increase,the current density distribution tends to be flat and the forming depth of the workpiece is decreasing.The gap flow field of electrochemical drilling was simulated and analyzed,The simulation results show the advantages of high speed spiral electrode in micro electrochemical drilling,which helps to discharge the reaction products,update the electrolyte,reduce or eliminate the taper of the hole.A series of micro electrochemical drilling experiments were completed by controlling the single variable method,the better micro-holes were successfully fabricated with the optimized parameters.The gap electric field and gap flow field in micro electrochemical milling were simulated,and a series of micro electrochemical milling experiments were carried out.The distribution of electric field intensity in the machining gap was analyzed,the width of the groove were predicted successfully under the primary,secondary and tertiary current density distributions.The flow field of electrochemical milling was simulated,the simulation results demonstrate high-speed spiral electrodes can improve the machining accuracy and efficiency significantly in the micro electrochemical milling.A series of experiments were carried out,the micro-grooves with good surface quality and high machining precision were successfully fabricated,which proved the feasibility of the micro electrochemical drilling and milling process proposed in this paper.