OPTIMIZATION SURFACE ROUGHNESS IN POWDER MIXED ELECTRICAL DISCHARGE MACHINING OF TITANIUM ALLOY.

To further improve the efficiency of electrical discharge machining of advanced materials, the possible technological improvement of the process is achieved by adding graphite powder to the dielectric. In this study, the Taguchi approach was applied to determine the effects of input parameters such as discharge current, pulse duration, duty cycle, and graphite powder concentration on surface roughness in machining titanium alloys. L9 orthogonal array, signal-to-noise ratio (S/N), and ANOVA were used to design and analyze the experiment. Discharge current was determined to be the factor that had the strongest influence on surface roughness. Based on ANOVA, pulse duration was the second influential parameter, followed by graphite powder and duty cycle. In addition, an optimum condition was found to improve surface roughness. A discharge current of 1.5 A, a pulse duration of 32 µs, a duty cycle of 30% and a powder concentration of 12 g/l resulted in minimum surface roughness. [ABSTRACT FROM AUTHOR]