Toward a better understanding of glass gravity-feed micro-hole drilling with electrochemical discharges

Spark-assisted chemical engraving (SACE) is a flexible, simple and inexpensive method for machining electrically non-conductive materials. SACE is particularly interesting because of the high drilling speed that can be achieved compared to other micromachining technologies. In this paper, the issue of drilling speed decreasing from 100 µm s−1 to 10 µm s−1 for micro-hole depths more than 200–300 µm is analyzed. To understand better the material removal mechanism, with the target to eliminate this limit, a model for the material removal mechanism as a hybrid mechanism combining local heating and chemical etching is presented and compared with experimental data. The comparison between the model and experiment allowed the estimation of the machining temperature to be around 600 °C.

[1]  Tetsuya Suto,et al.  High quality machining of ceramics , 1993 .

[2]  A. Gadalla,et al.  Modeling of Thermal Spalling During Electrical Discharge Machining of Titanium Diboride , 1991 .

[3]  C. T. Yang,et al.  Micro Hole Machining of Borosilicate Glass through Electrochemical Discharge Machining (ECDM) , 2001 .

[4]  V. Fascio,et al.  Machining of non-conducting materials using electrochemical discharge phenomenon – An overview , 2005 .

[5]  V. Fascio,et al.  3D microstructuring of glass using electrochemical discharge machining (ECDM) , 1999, MHS'99. Proceedings of 1999 International Symposium on Micromechatronics and Human Science (Cat. No.99TH8478).

[6]  Amitabha Ghosh,et al.  Mechanism of material removal in electrochemical discharge machining: a theoretical model and experimental verification , 1997 .

[7]  V. Jain,et al.  On the mechanism of material removal in electrochemical spark machining of quartz under different polarity conditions , 2008 .

[8]  G. K. Lal,et al.  Measurement of Temperature Transients in the Electrochemical Discharge Machining Process , 2003 .

[9]  L. A. Hof,et al.  The gas film in Spark Assisted Chemical Engraving (SACE) - A key element for micro-machining applications , 2006 .

[10]  Hitoshi Tokura,et al.  Ceramic material processing by electrical discharge in electrolyte , 1989 .

[11]  Hannes Bleuler,et al.  The current signal in spark-assisted chemical engraving (SACE): what does it tell us? , 2006 .

[12]  Hannes Bleuler,et al.  Geometrical characterization of micro-holes drilled in glass by gravity-feed with spark assisted chemical engraving (SACE) , 2007 .

[13]  Hannes Bleuler,et al.  Spark Assisted Chemical Engraving in the light of electrochemistry , 2004 .

[14]  Hannes Bleuler,et al.  A systematic characterization method for gravity-feed micro-hole drilling in glass with spark assisted chemical engraving (SACE) , 2006 .

[15]  Pulak M. Pandey,et al.  On the analysis of the electrochemical spark machining process , 1999 .

[16]  Ali Dolatabadi,et al.  Characterization and modeling of 2D-glass micro-machining by spark-assisted chemical engraving (SACE) with constant velocity , 2008 .

[17]  Herbert H. Kellogg,et al.  Anode Effect in Aqueous Electrolysis , 1950 .