Tool Design and Experimental Study on Electrochemical Turning of Nickel-Based Cast Superalloy

Abstract

With the rapid development of precision casting technology, more and more casted parts are used for critical components in aero-engines, such as turbine blades, supporting-case and other high-temperature engine parts. However, machining such alloy is very difficult by conventional mechanical methods. Previous studies have shown that electrochemical machining (ECM) is very suitable for efficient material removal of K423A, but is also vulnerable to stray corrosion. In this research, electrochemical turning (ECT), which is an extended form of ECM, is employed to process K423A cast revolving parts. The way of electrolyte-jet is implemented by an inter-jet cathode to improve machining localization and reduce stray corrosion. Simulation results show that the use of electrolyte-jet could effectively suppress the stray corrosion on non-machining areas. The diameter and outlet of the inter-jet cathode, and the cathode feed rate were designed, respectively. Experiments were conducted to verify the proposed method. It was confirmed that the stray corrosion of the non-machining area can be reduced significantly and the cathode feed rate can also be enhanced by using the proposed method. Finally, a simulated sample of a particular model of cartridge receiver with a larger machining height of 30 mm was fabricated successfully.