Study on effect of assist gas in electrolyte jet machining

Abstract

In electrolyte jet machining, by using a film flow formed after an electrolyte jet collides with a workpiece, the workpiece can be machined locally in the area of collision with the electrolyte jet by applying an electric current to the region. However, when the electrolyte flow rate is low, a hydraulic jump occurs near the jet and the film flow cannot be formed, thereby the workpiece cannot be machined locally. To solve this problem, we introduced an assist air jet coaxial to the electrolyte jet. The effect of the assist air jet on accelerating the radial flow of the electrolyte was clarified by hydrodynamic simulation. Machining experiments showed that the assist air jet has beneficial effects on machining stability at lower electrolyte flow rates, enabling higher aspect ratios in hole drilling and fabrication on concave surfaces.