Micro Slit Fabrication Using Magnetic-Assisted-ECDM and Parametric Optimization by Metaheuristic Algorithms

Abstract

Micro-slit fabrication of more than 1000 microns thick workpieces using the ECDM process is a complicated task since the ejection efficiency to remove the adhered particle dissolved from the workpiece in the electrolyte decreases with a higher depth of cut. Here micro-slit fabrication of more than 1200 µm thickness was carried out with magnetic field application on the ECDM. The magnetic field induces MHD convection on the electrolyte flow around the tool, which creates vorticity on the electrolyte. The centrifugal force created by the fluid when it rotates under MHD convection removes the material at a higher depth of cut. The machining performance in terms of maximum slit-cut thickness improves with increasing the magnetic field strength up to the optimum level because it induces the centrifugal force on the bubble, which enhances the gas film formation and discharge frequency. The experiments were conducted to fabricate a micro-slit with Taguchi L18 design and observe the effect of voltage, concentration, magnetic strength, and feed rate on MRR and width overcut. The magnetic field contributes significantly to the machining rate and overcut improvements. The metaheuristic algorithms, i.e., particle swarm optimization, differential evolution, and TLBO, applied and compared the optimal results of response parameters. The results reveal that the optimum value of MRR and WOC are the same, but the time and the iterations necessary to reach the optimal solution differ.