Influence of machining gap on both sides of blade in vibration-assisted pulsed electrochemical machining

The blades are important parts of any aeroengine, so the processing and manufacturing technology associated with blades has always been a high priority in aeroengine manufacturing. The electrochemical machining (ECM) of blades has become increasingly popular because there is no need to consider the strength, toughness, and hardness of the processing materials. Traditional ECM suffers from low dimensional accuracy and poor surface roughness. Thus, a low-frequency vibration of cathode tool is introduced to enhance bubble removal and electrolyte renewal. Due to the deformation of blade in ECM, the machining accuracy will be greatly reduced. This paper investigates the influence of gap difference which has been caused by electrolyte pressure and tool vibration on the deformation of the blade. The research results show that the deformation of blade increases with the increase of gap difference between cathode and blade. To restrain gap difference, a two-step processing test is conducted when blades were machined. It not only improves the processing efficiency, but also ensures the machining accuracy. The experimental results show that the total profile error of the blades is about 0.05 mm and the surface roughness is less than 0.13 mu m when the final gap difference is 0 mm, signifying high profile accuracy and surface quality.