Micro-structuring of glass with features less than 100 mu m by electrochemical discharge machining

Abstract

Micro-electrochemical discharge machining (ECDM) was studied in order to improve the machining of 3D micro-structures of glass. To minimize structures and obtain good surface microstructures, the effects of the electrolyte, the pulse on/off-time ratio, the voltage, the feedrate, the rotational speed, and the electrolyte concentration in the drilling and milling processes were studied. In ECDM, voltage is applied to generate a gas film and sparks on a tool electrode; however, high voltage produces poor machining resolution. To obtain a stable gas film over the whole surface of the tool at a low voltage, a new mechanical contact detector, based on a loadcell, was used; the immersion depth of the tool electrode in the electrolyte was reduced as much as possible. In this study, various micro-structures less than 100 mu m in size, such as circle divide 60 mu m micro-holes, a 10 mu m-thin wall, and a 3D micro-structure were fabricated to demonstrate the potential for micro-machining of glass by ECDM. (C) 2009 Elsevier Inc. All rights reserved.