Optimization of electric discharge machining process parameters using carbon nanotubes

Manufacturing of quality products at lower cost is the essential need for industries to arrive at the best manufacturing conditions, which can be obtained by using optimization techniques. In the present study, set of process parameters to be optimized are gap voltage, current, pulse ON time and multi walled carbon nanotube powder concentration in dielectric used in Electrical Discharge Machining (EDM) process. These parameters are investigated to identify the variations the performance characteristics of material removal rate and surface roughness. The material used for machining NAK80 Steel is a copper electrode. Based on the four factors at three levels, Taguchi's L9 orthogonal array is selected for carrying out the experiments. The objective of the present study is to get higher rate of material removal and lower surface roughness. The optimal solution is obtained by using Taguchi's Grey Relational Analysis method. MINITAB software was used to find the optimal levels of parameters in EDM process. The optimum result obtained was tested by carrying out the confirmation experiment. Based on the confirmation test, the improvements in material removal rate and surface roughness were 25% and 6.87% respectively. It is found from the present study that Taguchi's Grey relational Analysis is an effective technique to optimize the process parameters for Electric Discharge Machining.