OBRABOTKAMETALLOV Vol. 27 No. 2 2025 technology is influenced by Toff but to a lesser extent than Vg. The effect of pulse-off time (Toff) remains minimal, with a Delta value of 0.774. According to the ranking, Vg optimization should be the main priority for performance enhancement, followed by Ig management, while Toff modifications have minimal effect. Control of voltage stands as the critical parameter because it directly influences machining output, especially MRR, alongside SR and TWR performance. Voltage delivers the most significant impact on performance levels, followed by current. Changes in pulse-off time (Toff) have little impact on overall system operation because its duration plays a negligible role. Impact of process variables for utility function with raw data The main effects plot for means illustrates the influence of specific process factors on the mean utility values obtained from the experimental data. This plot helps determine the optimal levels of each parameter to enhance the effectiveness of the EDM process (Fig. 4). Fig. 4. Impact of process variables for utility function (UMRR, SR, TWR) with raw data Wire composition ECW (Levels: 3268, 4219, 5515, 5625, 5645, 5902): The mean utility value fluctuates across different ECW levels. The highest mean is observed at level 4219, suggesting this wire composition is optimal for better performance. Conversely, the lowest mean at level 5515 indicates a suboptimal wire material for machining efficiency. Gap current (Ig) (Levels: 8, 12, 16): the mean utility value increases steadily as the gap current increases. Higher current (16 A) results in better performance, likely due to faster material removal and enhanced efficiency. Lower current (8 A) leads to reduced performance, possibly because of insufficient spark energy for effective machining. Gap voltage (Vg) (Levels: 40, 55, 70): the mean utility value decreases significantly with increasing gap voltage. The lowest voltage (40 V) produces the highest mean, likely due to improved spark stability and reduced arcing. Higher voltages (70 V) degrade performance, possibly owing to unstable discharge conditions and poor machining control. Pulse-on time (Ton) (Levels: 13, 26, 38): the mean utility value slightly increases with longer pulse-on times. The highest level (38 µs) may improve material removal efficiency by enabling longer discharge duration. Lower levels (13 µs) result in marginally lower performance, potentially due to insufficient discharge duration.
RkJQdWJsaXNoZXIy MTk0ODM1