Implementation of a micro-electrical discharge machining system to fabricate TiO2 nanocolloid

Abstract

This study implemented a micro-Electrical Discharge Machining (micro-EDM) system based on Electrical Spark Discharge Method (ESDM) with real-time monitoring system to fabricate TiO2 nanocolloid. This system is relatively small size and low cost compared with industrial EDM machine. The real-time monitoring and control function of this system was achieved with VisSim software, an RT-DAC4/PCI card, and a designed servo circuit. Among the colloid prepared by micro-EDM system with two PID parameters, the colloid prepared using the PID parameters to get absorbance, average particle size, and suspensibility. The experimental results indicated that the colloid had absorbance of 0.187, ζ potential of -27.4 mV, average particle size of 223.9 nm, and percentage of colloidal particles smaller than 91.28 nm of 78.7% when the micro-EDM system Ton–Toff pulse period was set to 30–30 µs, the colloid production time was set to 20 min, and the PID controller parameter were set to Kp = 0.88, Ki = 0.045, and Kd = 0.035. TiO2 nanocolloid preparation in this study was completed in DW. The preparation process did not cause dust dissipation and was thus a green preparation method with low energy consumption.