Fundamental Research On The Application Of Precision ECM Technology To The Shaped Blind Hole With Large Depth Diameter Ratio

The special-shaped hole is widely used in aerospace,automobile manufacturing,chemical fiber machinery and many other fields,and most of them are made of hard to process materials,whose processing quality will have an important impact on the performance and life of parts.For some special-shaped hole structures,it is not only required to have a large depth diameter ratio,but also required to be half blind or full blind at one end,which is difficult to be processed by conventional methods.Electrochemical machining technology has the characteristics of no cutting force,no cathode loss,good surface quality and high processing efficiency.It has significant advantages for the processing of large depth diameter ratio special-shaped blind holes,and the larger the batch,the better the comprehensive economic benefits.In this paper,the simulation analysis and Experimental Research on the typical large depth diameter ratio semi blind hole structure and array blind hole structure are carried out,the main contents are as follows:1.The overall process plan of ECM for the special-shaped blind hole with large depth to diameter ratio was established,and the cathode structure of porous liquid passing tool was designed.Based on the simulation analysis of the electric field in the machining area,the optimal design of the cathode shape of the tool is carried out,which improves the problem of low precision in the electrochemical machining of the special-shaped hole;based on the simulation analysis of the flow field in the machining penetration stage,the structure of the through-hole of the tool cathode is improved,which is conducive to ensuring the stability of the flow field in the electrochemical machining at the outlet of the semi blind hole.2.In this paper,the electrochemical machining technology of large depth diameter ratio irregular semi blind hole and array blind hole structure is studied.Based on the simulation of gas-liquid two-phase flow in the machining process,the distribution of electrolyte velocity and air bubble rate in the machining gap passage is studied.The results show that the composite feed mode is conducive to strengthening the electrolyte renewal and improving the stability of the machining process.By optimizing the parameters of the electrochemical machining mode and the electrochemical process,the typical semi blind hole structure with a depth to diameter ratio of more than 10:1 and the typical array with a depth to diameter ratio of more than 20:1 are realized High quality and stable machining of column blind hole structure.3.The key technology of one-time electrochemical forming for the structural parts with large depth to diameter ratio of irregular semi blind hole and array blind hole has been completed.Compared with the existing EDM,the machining efficiency of the special-shaped semi blind hole structure can be increased by 8 times,and the machining efficiency of the array blind hole structure can be increased by 20 times,which can directly meet the final technical requirements,with significant technical advantages and good application prospects.