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Abstract Jet electrochemical (Jet-EC) milling, using a movable nozzle as the cathode, can fabricate complicated structures flexibly. With the dissolution restricted to a limited area by the electrolyte jet, high removal localization and good surface quality can be obtained. However, the edge of the machined groove is usually subject to stray corrosion because of the low current density in the edge area. In this paper, it is confirmed that the jet shape, which is determined by the working parameters, has a notable influence on the edge condition. Through experiments and analysis, the interrelation between the working parameters, jet shape and edge condition in Jet-EC groove milling is established. It is found that the stray corrosion on the edge can be reduced significantly by adjusting the jet shape, and the necessary conditions to completely eliminate the stray corrosion are established. Furthermore, based on the conclusions, a groove with both a sharp edge and a smooth surface is fabricated via a two-pass process. A deep groove (1.208 mm) with a sharp edge is produced via multiple-pass milling with downward cathode feeding. [ABSTRACT FROM AUTHOR]

Electrochemical drilling (ECD) is a useful method to produce small holes with a large aspect ratio on hard-to-machine materials. Recently, instead of using an acid electrolyte, more and more research has focused on neutral salt electrolytes because they are less harmful to the environment. However, more problems have been caused to the removal of waste products, especially in deep-hole drilling. Traditionally, an electrolyte flow with constant pressure control is adopted in ECD, which might result in the poor removal of waste products at depth because of pressure loss. In this paper, an ECD method with a constant electrolyte flow has been proposed to obtain a consistent ability to remove insoluble waste products from machining gap. Experiments of ECD with both constant electrolyte pressure and constant flow are conducted on workpieces of Inconel 718. Machining currents and the profile of machined holes are compared between the two methods. The results show that when a constant electrolyte flow rate is applied, the machining currents are much smoother and the profile of machined holes is also uniform. In addition, the pressure variation in the constant flow method increases linearly with machining depth. ECD with a constant flow also has an increased feed rate. [ABSTRACT FROM AUTHOR]