Research On Controllable Pulse Electrochemical Micromachining Technology

As the most typical product miniaturization and intelligent application,MEMS has been a hot topic for domestic and foreign scholars.Among them,the processing and manufacturing of micro-components is the core technical problem.Electrochemical micromachining technology is a special processing method for etching the workpiece by using the principle that the conductive metal is anode dissolved in the electrolyte.Ultra-short pulse electrochemical machining technology can greatly improve the accuracy of electrochemical machining,but its accuracy will be limited by ultra-short pulse power supply.This paper proposes a new controllable pulse electrochemical micromachining technology,which can control the precision of electrochemical micromachining in sub-micron order,avoiding the use of expensive ultra-short pulse power supply.A three-axis electrochemical micromachining test platform with high precision and high stability is developed The test platform includes three parts: motion control system,short circuit detection system and power supply system.Here,the development of three-dimensional electrochemical milling processing control and detection software system is completed.According to the small size of the micro-components,the hydrostatic machining method is selected,and the workpiece clamping method is optimized.A new controllable pulse electrochemical micromachining technology based on inductance is proposed.The adjustable inductance is introduced on the basis of the pulse electrochemical equivalent circuit,so that the initial first-order linear RC equivalent circuit becomes the LRC second-order oscillation circuit.Through the establishment of the mathematical model,the mechanism of obtaining high machining accuracy is analyzed.Using this technology,the electrochemical processing experiments of two-dimensional and three-dimensional microstructures were done,and sub-micron precision is obtained.A controllable pulse electrochemical micromachining technology based on capacitance is proposed.A tunable capacitor is introduced on the basis of the pulse electrochemical equivalent circuit to form a new coupling circuit.The mathematical model of the system is established and its processing mechanism is analyzed.The feasibility of obtaining high processing accuracy by the method is verified by electrolysis micromachining test.A controllable pulse electrochemical micromachining technology based on differential circuit is proposed.Through the introduction of the differential circuit,the pulse power supply output signal is differentiated,which effectively shortens the duration of the pulse current.The mathematical model of the system is established.Through the analysis of its output step response,the correspondence between the time constant of the differential circuit and the localization of the electrochemical process is obtained.The high-precision machining of the micro-gear structure is completed by this method,and the assembly and driving test of the micro-gear is completed.Through the study of the position of the inductor in the processing circuit,two different modes of electronic circuit and ion circuit are found.The transient response parameters that can directly reflect the electrochemical concentration are detected,and the real-time monitoring system of electrochemical concentration is designed according to this,which solves the problem of continuous short circuit caused by the decrease of concentration.The test and processing of the concentration monitoring system are completed,the feasibility of monitoring the electrolyte concentration change is verified.