Effect of Electrolyte Level during Electro Chemical Discharge Machining of Glass

Abstract

Electro chemical discharge machining (ECDM) is a hybrid machining process. This process has potential application for micro fabrication in nonconductive work materials such as glass. Micro fabricated holes and channels on glass are widely used in micro electro mechanical systems and bio medical devices. ECDM process takes place in an electrolytic cell consisting electrolyte upto certain level above workpiece. This electrolyte level affects the machining efficiency and quality of fabricated micro hole or channel. In this article, the electrolyte level was varied from 0.1 to 4 mm to investigate the effect on process responses of ECDM during fabrication of micro hole in glass. The process responses were material removal rate, depth of cut, heat affected zone and overcut. The effect of electrolyte level was characterized by spark discharge on voltage time wave form and microscopic images. The results revealed that an optimal value of electrolyte level is required for precise machining.

Critical review on tool wear and its significance on the µ-ECSM process

“…Similarly, with the rise in pulse-off time, the duration of sparks is reduced. 25 With low intensity and minimum duration of sparks, minimize the energy availability across the tool electrode, and hence tool erosion is decreased and improves the m-ECSM performance. 7,24 The straight polarity of the tool connection is generally preferable (the tool is made of cathode) for less tool erosion and a smooth surface finish of the product.…”

“…34 The effectiveness of m-ECSM increases as the tool rotates during the machining process by expanding the amount of fresh electrolyte solution available at a depth of the micro-hole. 25,35 Tool rotation enhances the machining accuracy by distributing the discharge energy uniformly and avoiding the focusing of the spark at a particular point. 36 Huang et al 35 observed that increasing the rotation speed from 6000 to 42,000 rpm results in the enhancement of hole diameter, quality of wall surface, and accuracy of the micro-hole.…”

“…39,40 Nevertheless, tool material having high surface roughness led to the formation of the larger size of hydrogen bubbles and resulted in the formation of thicker gas film and deteriorated the dimensional accuracy of micro features. 25 The wettability of the tool surface was also affected by the surface roughness and influenced the m-ECSM efficiency. 41 Some researchers even coated the tool electrode to avoid the side spark and maintain the machined profile's accuracy.…”

Review on Recent Advances, Research Trends, and Gas Film in Electrochemical Discharge-Based Micromachining

“…Tool contacts often result in high tool wear. Thus, precise control of the tool feed in a constant velocity method for acquiring the excellent features is necessary [99][100][101]. Schematic diagrams of these feeding mechanisms are shown in Fig.…”

“…It was found that with a 1 mm increase in electrolyte level, there was an increment of around 22.5% was observed in the overcut. Gupta [99] also studied the effect of electrolyte levels on various response parameters such as MRR, depth of cut, HAZ, and overcut. The electrolyte level effect was analyzed by voltage-time waveform and microscopic images.…”