Mass
ng (SEMM) technique. The SEMM system setup designed and developed indigenously allows performing two different electro micro-machining processes sequentially at one station without changing the tool and workpiece positions. A novel combination of micro electro-chemical discharge machining (µECDM) and micro electro-chemical machining (µECM) in a sequential manner introduced first time for micro-hole drilling in titanium alloy (Ti6Al4V). The machining of titanium alloy by µECDM process is a challenging task and not reported yet, hence the feasibility of machining of Ti6Al4V by µECDM process in different electrolytes and its combinations were experimented first. The effects of six commonly used electrolytes with concentrations of 1M and 9wt% on drilled hole characteristics were studied. The best suited electrolyte for drilling micro-holes in µECDM was selected by analyzing the hole depth, radial overcut, hole taper angle and the minimum time required to drill through holes in 400µm thick sheet of Ti6Al4V. The internal surface as well as the outer periphery of the hole produced by µECDM process becomes highly rough due to the presence of recast layer, cracks, micro-pores etc. in heat affected zone. The surface characteristics of µECDMed hole then improved by applying µECM process subsequent to µECDM process. The sequential combination of µECDM shaping and µECM finishing on developed SEMM setup results in improved dimensional accuracy, machining efficiency and surface quality of the hole produced.  Keywords: SEMM, µECDM, µECM, Ti6Al4V, micro-hole, shaping, finishing.