Design Of Electrolytic Plasma Polishing Device Of Titanium Alloy

Electrolytic plasma polishing has attracted the attention of metal surface processing industry in recent years,because of its high efficiency and environmental friendliness.Electrolytic plasma polishing has achieved a very good machining effect on stainless steel parts presently.The surface roughness can be reduced to Ra 0.06 ?m in only 1-2 minutes.However,when this technology is applied to other metal materials,the effect is far less obvious than that on stainless steel parts.This article takes titanium alloy as the research object.The reasons why the previous polishing experiments on titanium alloys failed to achieve the desired results were discussed.Then,an improved processing scheme was proposed and tested and verified.The equipment for polishing titanium alloy and the cleaning device after polishing are designed to solve the problem of electrolytic plasma polishing of titanium alloy.First,from the macro and micro perspective,this paper describes the process and removal mechanism of plasma polishing.It is pointed out that titanium and iron belong to two different metal types of valve metal and non-valve metal respectively,and n-type semiconductor oxide film will be produced on the surface of valve metal during machining,which makes the voltage cut-off show high resistance.It is the key of plasma polishing to restrain the oxide film on titanium surface.In this paper,adding fluorine ions and adjusting p H value are two ways to influence the formation of oxide film.According to the properties of titanium,a new processing method is proposed.In the first stage,the processing voltage is about 150 V,and in the second stage,the voltage is 200-350 V.According to the proposed processing scheme,the existing plasma polishing equipment for electrolytes has been modified to meet the needs of large-scale stepless voltage regulation.The control scheme of the test equipment with PLC as the core is established,and the selection of sensors,the design of lifting device and polishing fluid circulating device of the equipment,the programmingof PLC program and touch screen interface are completed.Then,three titanium alloys,TA1,TA7 and TC4,were selected as the test objects by orthogonal test.The concentration of two kinds of polishing salts,the voltage and time of two-stage processing were selected as the factors to be considered.Surface roughness and light reflectivity are selected as the evaluation indexes of machining effect.Finally,assuming that the experiment can achieve the desired effect,an automatic device for cleaning the polished titanium alloy parts was designed.Two schemes are considered: linear layout and surround layout.UR10 robot is selected to grasp and move the parts in the scheme of surrounding arrangement,and the joint angle of robot corresponding to each position is calculated.The motion of the robot is simulated in Vrep software.