Optimization design and experimental study of the flow field for precision ECM of blisks

Abstract

In the electrochemical machining (ECM) of the blisk, each blade must meet the machining requirements due to the blisk being an integral component. Therefore, maintaining the stability of the machining process is of great significance. However, in the current stage of the precision ECM process of blisks, it has been observed that blades may experience current fluctuation and occasional burn marks on the blade surface. In order to explore the causes of this phenomenon and solve the problem, this paper establishes a fluid-structure interaction mathematical model suitable for high-speed flow and geometric deformation during electrolytic precision machining. Meanwhile, a newly designed flow field and corresponding integrated fixture is proposed. Simulation results indicate that the new flow field successfully reduced the flow velocity difference between the concave and convex sides of the blade by 71 %, the equivalent stress on the blade decreased by 60 %, and blade deformation was reduced by 70 %. Meanwhile, corresponding experimental studies have been carried out. The experiment results show that the blade deformation decreased by 68 % with the new flow field form. 3D microscopic inspection and line roughness testing of the blade surface quality demonstrated that new flow field eliminated the current fluctuation and occasional burn marks phenomenon, and greatly enhanced the stability of the electrochemical fine machining process and the surface quality of the blades.