Basic Research On Electrochemical Machining For Inner Spiral Line Of Titanium Alloy Tube

With the advantages of high specific strength,low density and good corrosion resistance,titanium alloy is widely used in weapons equipment,aerospace and other important fields.Using titanium alloy material to design inner spiral tube can realize the lightweight of weapons,which can give full play to the advantages of flexible and fast of personal weapon and team portable weapon.However,the physical characteristics of titanium alloy such as high hardness,low deformation coefficient and low thermal conductivity lead to broaching machining inner spiral line of titanium alloy tube has problems of difficult heat dissipation,easy sticking knife,easy caving edge and high processing cost,which seriously restrict the application of titanium alloy inner spiral products in the field of weapons and equipment.The basic research on the efficient and high quality machining inner spiral line of titanium alloy tube using electrolytic machining technology has important theoretical research value and broad application demand.In order to realize the high quality one-off molding for inner spiral line of titanium alloy tube,based on the present research of domestic and foreign scholars,the analysis of anodic dissolution characteristics of titanium alloy electrochemical machining and the basic experiment of compound electrolyte formula is carried out in this paper.A downstream commutation cathode design method and optimizes the structure of cathode through liquid hole is put forward.The effect of process parameters on the machining quality and forming accuracy of titanium alloy tube inner spiral line is studied,and the efficient and high quality machining of titanium alloy tube inner spiral line is realized.The main research contents include the following aspects.The anode dissolution characteristics on electrochemical machining of titanium alloy is analysed,and the influence of processing voltage and electrolyte conductivity on current density distribution and electrolyte potential distribution is studied by electric field simulation.The single factor test method is used to study the influence of different electrolyte on the processing quality and efficiency of titanium alloy.Finally,the compound electrolyte formula of 10%NaCl+8%NaNO3+3%Na2HPO4 for TA15 titanium alloy is obtained,which effectively inhibits the appearance of pitting and achieves efficient and high surface quality electrochemical machining of titanium alloy.The cathode design method of electrolyte downstream commutation in cathode is presented to improve the uniformity of the electrolyte flow field.Through the flow field simulation,the effect of different diameters and oblique angles of cathode through liquid hole on machining gap is studied.A downstream commutation cathode structure with through liquid hole diameter of 3.5mm and inclination angle of 40° is obtained,which improves the flow velocity and uniformity of electrolyte in the working teeth region during electrochemical machining inner spiral line of titanium alloy tube.In order to study the influence of machining voltage,electrolyte pressure and cathode feed speed on surface roughness and forming precision,the basic experiment on electrochemical machining for inner spiral line of titanium alloy tube is developed.The L9(33)orthogonal experiment is carried out and experiment results are analysed using polar difference analysis method to obtain the optimal process parameter combination:machining voltage 10V,electrolyte inlet pressure 1.2MPa and cathode feed speed 20mm/min.According to the optimal process parameter combination,the electrochemical machining proof experiment for inner spiral line of titanium alloy tube is carried out.The stable and reliable processing of samples is achieved with forming accuracy of 0.04mm,surface roughness below 0.8?m.