Investigation into fabrication of microslot arrays by electrochemical micromachining

Abstract

Maskless electrochemical micromachining (EMM) is a prominent and unique surface texturing method to fabricate the arrays of microslots. This article investigates the generation of microslot arrays using maskless EMM method. The developed prototype maskless EMM setup consists of EMM cell, power supply connections, electrode holding devices and constricted vertical cross flow electrolyte system for the fabrication of microslot arrays economically. One textured cathode tool with SU-8 2150 mask is used to produce 22 microslot arrays. Influences of EMM process parameters including voltage, electrolyte concentration, inter electrode gap, flow rate and machining time on the machining performance that is, width overcut, depth and surface roughness (Ra) of microslot arrays are investigated. For lower width overcut, controlled depth, and lower surface roughness, machining with lower voltage, lower electrolyte concentration, lower inter electrode gap, higher flow rate and lower machining time are recommended. From the analysis, it is observed that the best machining conditions including inter electrode gap of 50 μm, applied voltage of 6 V, electrolyte concentration of 20 g L−1, flow rate of 5.35 m3 hr−1 and machining time of 1 min fabricate regular microslot array with mean width overcut of 24.321 μm, mean machining depth of 10.7 μm and mean surface roughness of 0.0101 μm.