Plane Machining by Inner-Jet Electrochemical Milling of TiB₂/7050 Aluminum Matrix Composite

Abstract

Electrochemical milling (ECM) is an ideal technique for machining thin-walled structural parts of aluminum matrix composites. Adopting a reasonable tool cathode structure, feed rate, and processing method can improve the machining efficiency. In this study, a tool cathode with a reasonable structure was selected through flow field simulation. Then, the material removal rate (MRR) and surface roughness were studied using various ECM parameters. Finally, the transverse movement and processing method in which the starting position was rotated 90° were studied, and a plane of 59 × 59 mm was machined. The experimental results show that using an appropriate tool cathode can create a more uniform flow field. The MRR was 168.6 mm3/min and the surface roughness (Ra) was 3.329 µm at a feed rate of 30 mm/min. For machining larger plane structures, a transverse movement of 7 mm is verified to be the most suitable because of the best smoothness in the middle of the two processes. By using the same machining method and rotating the starting position 90°, the flatness of the processing plane decreased from 0.296 mm to 0.251 mm, a reduction of 15.2% compared to that obtained in the first processing.

Keywords

• TiB₂/7050
• electrochemical milling
• flow field simulation
• material removal rate