Multi-objects optimization in µ-EDM using AlCrNi-coated tungsten carbide electrode for Ti-6AL-4 V

Titanium alloy (Ti-6Al-4 V) is widely used in a number of fields such as medical, aeronautical, and nuclear fields. Since the surface finish should be enhanced as much possible in efficient way, the micro EDM process can be used for machining such materials. The process mechanism can be enhanced by utilizing the coated electrode in the process. In the present study, an effort was made to investigate the effects of process parameters on drilling titanium alloy with aluminum chromium nitride (AlCrNi)-coated aluminum electrode in micro EDM process. An optimization approach was also implemented using Taguchi-DEAR approach. From the experimental interpretation, the conclusions were made as follows. The AlCrNi-coated aluminum electrode can enhance the machinability of micro EDM process. The optimal combination of voltage (140 V), capacitance (10000pF), and spindle rotation (200 rpm) could provide better quality measures among the chosen variables. The moderate voltage and capacitance can remove the material effectively with lower overcut, since the electrical conductivity can effectively enhance the conductivity of the plasma energy column. The coated electrode can create the tiny craters with uniform energy distribution.