dc.description.abstract | Monocrystalline silicon, being hard, brittle and semi-conductive, poses problems to traditional machining. In this study, it is processed by electrochemical discharge machining (ECDM), which involves high-temperature melting and accelerated chemical etching under the high electrical energy discharged on the electrode tip during electrolysis. To enhance efficiency and precision in monocrystalline silicon micro-hole drilling, square helical tool electrode and pulse voltage are used with sodium hydroxide as the electrolyte. Experimental results show that square helical tool electrode is superior to helical tool electrode for ECDM of monocrystalline silicon. Greater machining efficiency and better micro-hole quality can be achieved by its unique geometrical design which enables stable and regular electrical discharge. It is also have excellent quality to machining composite silicon-based material by using helical tool electrode quality .Pulse voltage with appropriate proportion of pulse-on and pulse-off time also ensures rapid replenishment and good circulation of electrolyte as well as efficient debris removal. Sodium hydroxide can replace hydrofluoric acid or ammonium fluoride as the electrolyte. Not only does it incur lower costs, it is also safe and environmental friendly.
Copper plating, a safe and inexpensive technology with simple operation, has been widely applied to interlayer connection of electronic components via through holes, and blind holes. This study proposes coupling Electrochemical Discharge Machining (ECDM) with rotation and penetration of electrode for fabricating plated hollow holes. Not only does this approach combine hole-making and electroplating in a single process, which saves time, it also improves conductivity, heat dissipation and component assembly, thus enhancing processing efficiency of plated holes in industrial applications. Experimental results show that rotation and penetration of tool electrode contribute to better plating effect, solving the problems including accumulation of plating solution at hole entrance and plated layer of uneven and coarse structure. Finally, ECDM under machining voltage, 0.3 V; machining time, 60 min; and rotational speed of electrode, 100 rpm yielded plated hollow holes with even coating and flat smooth hole wall surface. | en_US |