INVESTIGATION OF ELECTRODE WEAR AND SURFACE QUALITY IN POWDER MIXED ELECTRICAL DISCHARGE MACHINING (PMEDM) WITH LOW-FREQUENCY VIBRATION APPLIED TO THE WORKPIECE

The integration of low-frequency vibrations into the powder-mixed electrical discharge machining (PMEDM) process has the potential to substantially improve the efficiency and productivity of the machining process. This study focuses on exploring the impact of such vibrations on the process mechanics and outcomes, specifically targeting the machining of SKD61 tool steel. To achieve this, a comprehensive analysis was conducted using an innovative approach where titanium powder was mixed into the dielectric fluid, and red copper (Cu) was employed as the electrode material. The key process parameters investigated include discharge current (I), pulse-on time (Ton), powder concentration (Cp), flushing pressure, as well as the frequency and amplitude of the applied vibrations. A Taguchi L25 orthogonal array was employed to systematically design the experiments and to analyze the effects of these parameters on the process performance. The study reveals that the concentration of titanium powder in the dielectric fluid plays a critical role in the deionization mechanism, significantly influencing the electrode wear rate (EWR). Furthermore, the introduction of low-frequency vibrations enhances the interaction between the electric spark and the titanium powder, leading to notable improvements in the mechanical properties of the machined surface layer. This research contributes novel insights into the PMEDM process by demonstrating how low-frequency vibrations, when combined with powder-mixed dielectrics, can be leveraged to optimize machining outcomes. The findings offer valuable implications for advancing the precision and efficiency of EDM processes in industrial applications.