Cathode Design And Technological Experiment Of Numerically Controlled Electrochemical Machining Of A Large-scale Integral Impeller

Numerically Controlled Electrochemical Machining(NC-ECM) is a new kind of manufacturing technology which principle is based on the combination of Electrochemical Machining(ECM) and Numerically Controlled techniques. It not only has the advantage of traditional ECM, but also has the advantages of Numerically Controlled techniques. Components of high-strength and heat-resistant alloys can be machined by it with high efficiency, which made it playing very important role in the aero-engine industry. Based on the former research, the manufacture of large-sacle integral impeller of aero-engine by NC-ECM is studied in this thesis.The large-scale integral impeller is a kind of integral impeller which diameter is larger than 500mm. Firstly ,the structure of integral impeller ,its material and development trend are introduced, then the machining methods of integral impeller are introduced in classification, through comparing these methods with each other, the status of NC-ECM is affirmed in machining the large integral impeller.As a result of the limited movement distance of the main-shafts, putting forward a simple, reasonable plan on the premise of not changing the machining tool by designing the structure of workpiece, linking pipe, and the layout of the parts. Then making a model of the large-scale integral impeller by UG software. In considering of some common problems in complex surface modeling, making some resolutions to it.On the basis of analysis of the channel between two blades by UG software, designing the cathode spurting fluid from inside. The key process issues, such as the short circuit and the ununiformed flow field are discussed. The effective improvements of the outside structure and fluid flow of the cathode are given. It not only shortens the cycle of the design and machining of the cathode, but also improves the quality of the products.The appropriate processing parameters are selected by experiments and the results are deeply analyzed. The test sample is made. Finally, as a result of the high accuracy and good surface quality of the pulse electrochemical machining (PECM), some preliminary research of PECM is done, which offers a good foundation for the further precision machining.