Performance of electrochemical micromachining of copper through infrared heated electrolyte

The application of Infrared (IR) light in electrochemical micromachining (EMM) is to focus the machining to confined areas so that material removal and productivity is improved. Predominantly, the localization mechanism in electrochemical machining (ECM) for material removal is determined by the temperature. In this study, a novel method of heating the electrolyte using IR has been attempted in EMM for the first time. IR light is considered for indirect heating of sodium nitrate (NaNO₃) electrolyte. Machining parameters such as machining voltage, duty cycle, and electrolyte concentration are varied by keeping the current and electrolyte temperature constant at 1 A and 37 ± 0.5°C, respectively. The effect of these parameters on machining rate and overcut is studied. The result showed that the machining rate for heated electrolyte is 4.2 times better than the electrolyte at room temperature for 25% duty cycle, 35 g/L electrolyte concentration, and 9 V machining voltage. The change in electrolyte conductivity of heated electrolyte solution shows considerable effect on overcut. Field emission scanning electron microscope (FESEM) images show much difference in surface structure for electrolyte at room temperature and heated electrolyte. The findings provide valuable understandings on the use of IR light to heat the electrolyte in order to improve the performance of EMM systems.