A Study on Wire Electro-Chemical Discharge Machin ing (1 st Report)

Machining Characteristics of Glass and Ceramics

Abstract

This paper deals with a new method of wire electro-chemical discharge machining of non-conductive materials such as ceramics.
The method is achieved by combining the cutting technique of wire-EDM with electrochemical discharge machining used for drilling non-conductive materials such as glass, diamond and ruby immersed in an electrolyte. In its method a molybdenum wire of 0.1mm in diameter is employed as one electrode and platinum wire of 0.5mm in diameter as the other electrode. The electrolyte of KOH solution is fed to the contact area between the work specimen and the molybdenum wire.
Glass and ceramic plates as work specimens can be successfully cut by the electric arcs generated along the contact line between the work specimens and the wire electrode in the electrolyte.
The effects of the polarity of the electrodes, the types of the current, the voltage applied to the electrodes, and the conoentration of the electrolyte on the cutting rate and the kerf width are examined.
The maximum cutting rate of silica glass (1.0mm in thickness), that of Al₂O₃ ceramic (1.2mm in thickness), that of Si₃N₄ ceramic (1.2mm in thickness) and that of ZrO₂ ceramic (1.2mm in thickness) are 6.8mm/min, 0.3mm/min, 0.67mm/min and 0.2mm/min, respectively, The kerf width at the maximum cuting rate of silica glass, that of Al₂O₃ ceramic, that of Si₃N₄ ceramic and that of ZrO2 ceramic are 0.20mm, 0.31mm, 0.45mm and 0.13mm, respectively.
The results obtained show that the method is effective for cutting glass and ceramic materials in two dimensional contour.