Research On Electrochemical Milling Of TC4 And Ti40

Titanium alloys are widely used in aerospace,military manufacturing and civil field due to their unique corrosion resistance and high strength ratio.Electrochemical milling technology can be used for various titanium alloy parts with complex shapes using cathode with simple shape.The method of electrochemical milling of titanium alloys has been increasingly noticed by more and more researchers due to its flexible.However,the passive film formed on the surface has an important effect on the electrochemical milling process because the surface of titanium alloy will undergo the process of activation-passivation-superpassivation.In this paper,the electrochemical properties of titanium alloys and the breakdown behavior of passive film were studied,and the simulation of the groove electrochemical milling process and a series of basic experiments were carried out.The completed research contents mainly includes the following aspects:?1?The polarization curve and the current efficiency curve of titanium alloy TC4 and Ti40 were conducted which would provide basis for simulation.The breakdown behavior of the passive film formed on the surface of TC4 and Ti40 materials in 20%NaNO₃ electrolyte was investigated to obtain the breakdown time and the quantity of electric charge needed for the breakdown of the passive film.?2?The simulation analysis for the electrochemical milling of the groove process was carried out.A three-dimensional model of groove in electrochemical milling process was established,then the profile of the groove and the curve of current density and electric quantity with time at any point on the anode surface can be obtained.Based on the experiments,the electric quantity values needed for the breakdown of passive film during the process can be determined,then the breakdown time of passive film at any point on the anode surface can be also determined.?3?The basic experiments of electrochemical milling of TC4 and Ti40 materials were carried out to study the effects of machining gap,machining voltage,feed rate of cathode,milling layer thickness and transverse spacing parameters on the machining of grooves and profiles.The optimum range of processing parameters and the selection strategy of processing path are determined by a series of parameter tests and comparison of results.