Statistical investigation of surface roughness and kerf on wire electrical discharge machining performance

This paper describes statistical investigation to optimise the process variables such as pulse duration (pulse on), pulse period (time between pulses), and peak current that affects the output response surface roughness (SR) and kerf (k) on WEDM through grey relational analysis (GRA). Taguchi L16 design matrix has been used to carry out the experimental work. Response surface methodology (RSM) is used to develop the empirical models from the experimental data. Analysis of variance (ANOVA) is used to check the adequacy of the developed models. Based on statistical analysis, it has been found that peak current and pulse off time has a positive influence on SR while pulse on time has a negative influence, as well as peak current and pulse on time, has a negative influence on kerf while pulse off time has a positive influence. Confirmation test shows the application of the optimisation technique for predicting optimum conditions to obtain better output responses. [Submitted 27 January 2018; Accepted 10 May 2018]