| Numerically controlled electrical machining is a new manufacturing method which combine numerically controlled electrochemical machining (NC-ECM) to numerically controlled electrical discharge machining (NC-EDM). This method plays an important role in the machining of closed integral impeller because it has not only the high productivity of NC-ECM, but also has the high precision and high stabilization of NC-EDM. It is used more and more in the machining of impellers which have complex profile and closed structure. NC-ECM is a key step to increase the profess efficiency and lower the cost of the manufacturing. Taking a 3D-flow closed integral impeller as the study object, the experiments of NC-ECM were made in this thesis. The following work has been done:1) The three-dimensional modeling of the 3D-flow closed impeller has been done. Based on the modeling, the analysis of the channel has been done, and to simplify the design of the cathode and its movements, the way of manufacturing by multi cathodes was introduced. These cathodes and their movements have been designed.2) On the basis of the machining motion simulation which was achieved via secondary development of UG, the processing simulation has been done, the profile and the movements of the cathodes were checked, and also it was checked that if there was any interference in the NC-ECM process. And along with the simulation, the cathode and its movements were modified, and the times of the experiments were lessened, the time of the preparing was shortened also.3) The appropriate processing parameters were selected by several experiments, and the profile of the cathode were modified optimally to fit the manufacturing practically. In order to solve the difficult problems in the experiments, the method of drilling some fabrication holes before NC-ECM was proposed and it improved the stability of the flowing field well. And finally the NC-ECM of 3D-flow closed integral impeller was finished.
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