Effects of Helical Tube Electrode Structure on Mixed Machining Product Transfer in Micro-Machining Channel during Tube Electrode High-Speed Electrochemical Discharge Machining.

In tube electrode high-speed electrochemical discharge machining (TSECDM), mixed products are constantly produced in the narrow machining gap by simultaneous discharge erosion and electrochemical dissolution. For the high-efficiency removal of these products from the machining gap, a tool electrode with an optimized helical structure was utilized in TSECDM in this study. Firstly, the concentration distributions of the processed products in the machining gap using tube electrode tools with three typical helical structures were studied through the simulation of solid-liquid coupling; this showed that a trapezoidal helical structure benefited the reduced accumulation of products in grooves and the effective removal of products from the machining gap. Secondly, the main geometric parameters of the trapezoidal helical structure, including the helical groove depth, pitch, and tooth angle, were optimized by gap flow-field simulation to enhance the removal effect on processed products. Finally, it was verified that the trapezoidal helical electrode showed a definitive and significant advantage over the ordinary cylindrical electrode in effectively removing processed products from the machining gap by the comparison of flow-field simulations and actual machining experiments.