Research On High Efficiency NC Electrochemical Machining Technology For 30CrMnSi Material

With the rapid developlent of aerospace industry,higher requirements have been put forward for metal materials.The traditional processing methods are no longer applicable which arc limited by hardness,residual stress and micro-cracks.Electrochemical machining(ECM)teclenology is based on the principle of anodic dissolution of conductive metals in electrolyte.It has many advantages,such as no material hardness limitation,no tool loss,no residual stress and metamorphic layer,etc.It has been widely used in processing difficult-to-machine metal materials.To solve the problems of long processing cycle and high cost of time and equipment in the lightweight processing of xxxParts(30CrMnSi)by WEDM in Xi'an Aero Engine CoMPany.a high-efficiency electrochelical machining(ECM)process plan is studied.The main work is as follows:The compound machining scheme of "electrochemical interpolation+electrochemical ring milling" is formulated,which can effectively eliminate the corrosion by electrochemical interpolation and improve the quality of electrochemical machining by electrochemical ring milling.Tool electrodes for electrochemical interpolation and electrochemical ring milling are designed and manufactured.Flow field distribution in the process of two processes is simulated by COMSOL Multiphysics,the entrance pressure of electrolyte is detennined,and the electrode structure is modified based on the simulation results.In order to understand the ECM forming law of 30CrMnSi material,single factor experiments are carried out.On the basis of factor experiment research,the physical coupling simulation orthogonal table is established,and the current density under the combination of electrical parameters and process parameters in the orthogonal table is simulated.The open-circuit potential of cathode and anode materials is measured by electrochemical workstation.The simulation results of current density and potential measurement data are introduced into the theoretical formula of balanced gap,and the material specificity of 30CrMnSi is established.Balanced gap model of electrochemical interpolation and electrochemical ring milling.The optimal experimental parameters is obtained based on the relationship between the material removal rate and the clearance of the equilibrium clearance model.According to the optimized electrical and technological parameters,the experiments of electrochemical interpolation and electrochemical ring milling are carried out under the condition of mixed solution as electrolyte.The experimental results show that the time of electrochemical interpolation is short to 16 minutes,and the surface roughness of the workpiece side wall is 5.526?m after electrochemical ring milling.Through theoretical calculation and experimental verification,a balance gap model for 30CrMnSi material is e,and the process parameters of electrochemical interpolation and electrochemical ring milling are optimized.Electrochemical interpolation can significantly reduce the processing time,and electrochemical ring milling can significantly improve the surface quality of the side wall of the workpiece.This research provides a new processing scheme to solve the problems of the long processing cycle and high cost of Aeronautical 30CrMnSi processing,and also provides a direction for efficient electrochemical machining of difficult-to-nachine metal workpieces.