Abstract
In this paper, the authors propose a numerical method to analyze the machined shape in the Electro-Chemical Jet Machining (ECJM) by calculating the distribution of electric potential in the electrolyte using the Finite Element Method (FEM). In this ECJM, a high pressure electrolyte is jetted from a fine nozzle whose position is numerically controlled against the workpiece, and a pulsating machining current is supplied in the working gap for micro-fabrication.
At first, assuming the voltage drop in the electrolyte the theoretical machining current is calculated by means of integrating the current density, which can be obtained from the potential distribution, over the surface of the workpiece. Secondary, the assumed voltage drop is adjusted so that the theoretical machining current should coincide with the measured machining current. Then, the current density distribution over the surface of the workpiece is recalculated using the corrected voltage drop. Lastly, from the current density distribution the machined shape is found by taking the equivalent dissolution valence of the workpiece and the current efficiency, both of which are obtained from the measured relationship between the current density and the material removal rate, into account. It was found that the shape obtained by the numerical calculation coincided well with the experimental result.
