Abstract：Electrochemical machining (ECM) has played an important role in the efficient and precise manufacturing of core components such as aero-engine blades or blisks in Europe and the United States. Using the traditional ECM, the cathode tools for machining blade concave and convex surfaces move towards each other, and the profile of the blade and the contour of the leading and trailing edges are processed at the same time. At this time, the accuracy of blade profile is easy to ensure, while the accuracy of leading and trailing edges is low. In this paper, a stepwise pulsant precision ECM method for blade is proposed, which aims to further improve the profile accuracy of blade and the contour accuracy of leading and trailing edges. The method is divided into two different stages. Firstly, the blade surface is machined precisely by pulsant dynamic variable parameter ECM mode, and then the leading and trailing edges are machined by micro pulse ECM mode. The research of the above two stages in machining mechanism and processing experiment are described in detail. Aiming at the problem of passive diversion in the traditional radial flow field, an active diversion axial flow field is proposed. The experimental results indicate that this method shows favorable process effects. The machining error of the concave surface and convex surface is – 0.013 – 0.025 mm and – 0.003 – 0.030 mm, respectively. The machining error of leading edge is – 0.034 – 0.041 mm, the machining error of trailing edge is – 0.038 – 0.034 mm, and the surface roughness of the concave profile and the convex profile are respectively Ra0.333 μm and Ra0.287 μm. The proposed method provides a new solution for the realization of high-precision manufacturing of aero-engine blades, and can be used for machining of other complex-shaped components.
2022, 
