The Analysis of Particle Size Effect on Performance of WC/Cu P/M Compact Sintered Electrode in EDM Process

The main aim of this study is to evaluate the influence of particle size variations on electric discharge machining (EDM) electrodes made with a combination of Tungsten carbide (WC) and Copper (Cu) powders using the powder metallurgy (P/M) method. The electrodes are in cylindrical shape of 15 mm diameter and are made with following sizes i.e., Nano Particles (NP), a mix of Nano and Micron Particles (NMP) and Micron Particles (MP). Electrodes, thus made in combinations were used to study the performance during surface modification of Inconel 718 alloy using EDM. The electrodes were made with wt% 40, 50& 60 of WC and the rest is Cu, whereas the compaction ranges 200-400Mpa. Among the unconventional machining processes, EDM is the most preferred surface modification process to machine very hard materials like Inconel 718 alloy. Machining was conducted by varying parameters viz., pulse on time, polarity, peak current, %WC in tool composition, Particle size, and compaction pressure. The performance indicators in the present investigation are material removal rate (MRR) and tool wear rate (TWR). The results were analyzed using MINITAB 14 software, and it was noted that the improvement in MRR was due to the influence of particle size and peak current. A highest MRR of 9.90 mg/min was attained with NP electrode and a peak current of 13A. The highest TWR of 20.70 mg/min was also observed at the machining condition where highest MRR was observed. The results of the MRR and TWR values show the significant influence of all the six process variables on EDM process. (C) 2021 Jordan Journal of Mechanical and Industrial Engineering. All rights reserved