Shestakov I.Ya., Voroshilova M.V., Voroshilov D.S. Looking at the surface quality during local ammonium nitrate electrolytic machining

Abstract

This article describes the results of the research into electrolytic machining of 1201 aluminium alloy in aqueous solutions of ammonium nitrate. Having analysed some of Russian and international research papers on electrolytic machining, the authors came to the conclusion that studying the shape of an EDM tool (including its simulation) presents an important problem. A variety of factors determine the shape of an EDM tool, such as the electrolyte flow rate, the electrolyte temperature, the current density. The electrode coating is also important as it helps improve the quality of machining. The research conducted helped determine the effect of the electrolyte composition, current density and flow rate on the surface quality along the anode-to-cathode distance. The experiments showed that the flow rate of ~0.55 m/s provides the minimum roughness and the excessive flow rate largely affects the surface quality. It was found that the use of a circular cross-section cathode tool leads to the current spreading across the surface of the workpiece which reduces the machining accuracy and surface roughness in the transition zone. The use of a cathode with a flat face helps localize the current density on the treated surface thus increasing the machining accuracy. It was established that a cathode tool with a titanium oxide flat face helps reduce the surface roughness. The research helped identify the best electrolytic machining technique for large thin-walled parts when using a titanium cathode tool with a semiconductor coating. Below are the recommended electrolytic machining parameters: current density between 14 and 26 A/cm2, flow rate between 0.3 and 0.6 m/s, electrolyte temperature 25 – 30°C. The following aqueous solution is recommended for electrolyte: 15% NH4NO3 + 2,5% Na3C6H5O7.

Keywords

Electrolytic machining, EDM tool, cathode, roughness, electrolyte, flow rate, current density.

Ivan Ya. Shestakov – D.Sc. (Eng.), Professor

Siberian Federal University, Krasnoyarsk, Russia. Phone: +7 (391) 206-37-78. Е-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Marina V. Voroshilova – Assistant Professor

Siberian Federal University, Krasnoyarsk, Russia. Phone: +7 (391) 206-36-18. Е-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

Denis S. Voroshilov – Ph.D. (Eng.), Associate Professor

Siberian Federal University, Krasnoyarsk, Russia. Phone: +7 (391) 206-37-31. Е-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.

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