Research On The Application Of Electrolytic Polishing Technology In Compressor Vane Remanufacturing

Remanufacturing is a new area of machinery manufacturing which can upgrade the old mechanical and electrical products by means of anvanced recovery methods, such as laser cladding, thermal spraying and cold welding. Many countries pay much attention to the remanufacturing because mechanical and electrical products obtained through remanufacturing are better than new products in terms of properties and it can save much energy and many materials. The parts of remanufacturing have the characteristics of high hardness and difficult processing. Therefore traditional processing could hardly fullfill the demand of precise processing. It is free from the constraint of hardness of materials and increasing surface residual stress of workpiece and provides high machine precision. Thus the study of Electro-polishing is playing a increasingly important part in remanufacturing. Electro-polishing follows the principle of corrosion electro-chemistry and reaches the goal of polishing and processing by controlling the parameters such as electrolyte current density temperature and spacing between anode and cathode. Currently the study aims at two aspects:one is composite technology, that is electro-polishing combined with ultrasonic, electromagnetic and electric pulse. The other is the study on electrolyte.The composition of electrolyte and parameters of electro-polishing have great influences on the effect of polishing.The laser cladding layer of Fe substrate and FV520B Ni substrate can be determined through linear sweep voltammetry and TAFEL. The same to45Ni substrate, Fe substrate and the polarization curve of FV520B cold welding repairing layer. By analyzing formulation rules of passivation film of chromic acid, perchloric acid and hydrochloric acid in the view of electrochemistry, we can get the optimal polarization curve. Applying the best results above to electro-polishing can get low surface roughness and higher luster. In conclusion, using the polarization curve, we can get the parameters of electro-polishing quickly.The corrosion rate was measured by weighing in this article. We derive the influences of voltage and hydrochloric acid on corrosion rate. As with the wokpiece low in requirements, the processing speed can be improved by enhancing the voltage and the concentration of hydrochloric acid.We study the principle of electro-polishing, processing parameters and processing speed through COMSOL simulation, potentiodynamic scanning voltammetry and weighing. We can quickly find out the method of electro-polishing by analyzing metal passivation zone. Weighting can help measure the speed of corrosion and obtain the factors which influence the speed of processing.The distribution features of current density and corrosion speed can be demonstrated through COMSOL two-dimensional simulation test, that is, the more raised the position is, the higher of the current density and corrosion speed there will be. The orthogonal test shows the sequential consequences of electrode voltage, conductivity and distance between electrodes on current density and corrosion speed and also gives the best combination. With the3D simulation of leaf blade, the results show that due to the complication of the shapes of leaves, the electro-polishing of all parts of leaf blade can’t be controlled easily. So local polishing effect is better than global polishing.