Influence of High Duty Ratio and Frequency in WECM Employing In Situ Fabricated Wire Electrode

Abstract

To adapt with today's rapidly changing world, fabrication of intricate microparts is becoming an urgent need. Manufacturing of these microparts with stringent requirements necessitates the early adoption of different microfabrication techniques. Wire electrochemical machining (WECM) is such a process which removes excess metal by dissolving it electrochemically. This process can easily generate features downscaled to micron ranges and offers several advantages like the requirement of very simple setup, fabrication of accurate complex microfeatures without undergoing any thermal stress, burr formation, and tool wear, which make it superior from other existing micromachining processes. However, this process is new, and little is known about its applicability and feasibility. Hence, the present work is directed towards developing suitable WECM setup to fabricate microfeatures by introducing proper means for enhancing the mass transport phenomenon. The tungsten tool wire for machining has been in situ etched to a diameter of 23.43 μm by a novel approach for retaining its regular cylindrical form and has been implemented during machining. Moreover, the influences of high duty ratio and applied frequency have been investigated on the corresponding width of the fabricated microslits and the experimental results have been represented graphically where the minimum width of the microslit is obtained as 44.85 μm. Furthermore, mathematical modeling has been developed to correlate duty ratio and applied frequency with generated slit width. Additionally, the mathematical modeling has been validated with practical results and complex stepped type microfeatures have been generated to establish process suitability.