Design Of Rotary Flow Field And Study On Technological Regular Of Electrochemical Machining For Closed Integral Structure

In order to make the equipment in national defense industry have small size, high hit rate, long service time, low cost and good performance, it plays an important role in the application of closed integral structure., and it have found more and more application in advanced aerospace, weapons and equipment engine at present. The closed integral complex structures, being narrow, bending and twisting of the vortexpath between blade, machinability poor and workpiece materials hard to cut, have become a difficult manufacturing problems in the world..Recently,Combining NC electrochemical machining (ECM) and electric discharge (EDM) has become a hot research topic.In order to further improve the machining efficiency and surface roughness of closed integral structure, the combination of ECM, EDM and electrolytic polishing was presented in this paper, and a scheme of digging and shaping simultaneously in the first step-ECM was proposed, The simulation for different schemes of rotation flow field in the closed integral structure based on COMSOL software were carried out. The results show that the effect of the reverse flow scheme 4 in which the included angle between the two inlet mouths is 90° with 3mm in axial is superior to others in which the two inlet mouths with different angles are all on the same plane,and the condition above design is that the inlet mouth is 2 times the size of outlet mouth, from the direction of the top and abdomen gap rotary flow.In the ECM process the material is S-03 special stainless steel, initial pressure 0.5MPa, temperature 35℃, voltage 14V,15V,16V and 17V. The experimental results show that the higher accuracy can be obtained under lower voltage.However,the lower the voltage is, the slower the corrosion speed of the workpiece. And the smaller the machining gap, a short circuit may be caused. On the ground of the experiments, voltage 16V is suitable for S-03 special stainless steel. Processing results indicate that the efficiency of the combine of ECM-EDM and electrolytic polishing is 36% higher than the originally single EDM in which processing ten vortexpathes have to be consume 300 hours, while in combine of ECM-EDM processing ten vortexpathes only 23 hours by ECM (including installation auxiliary time) and subsequent EDM 170 hours.Finally, the electrolytic polishing for the ten vortexpathes were performed with investigating technological regularity by ajustining the parameters of electrolytic polishing.,The efficiency of electrolytic polishing is the best when the polishing voltage is 7V and other parameters are the same. When the ten vortex pathes were polished to Ra1.6um, the polishing time is 10 hours, when to Ra0.19-0.37um the polishing time 32 hours.Compared with the original factory process, the total polishing efficiency and surface roughness of processed by the combine of ECM, EDM and electrolytic polishing were significantly improved.