Influence of thermo-electrical property of materials on Powder Mixed Electrical Discharge Machining

Abstract

Powder Mixed Electrical Discharge Machining (PMEDM) is considered as one of the viable methods to machine the materials which are hard and tough but with appreciable thermo-electrical properties. In PMEDM, it has been established that machinability is enhanced by adding additives in the form of fine powders in the spark gap of EDM process. In this investigation, the role of the thermo-electrical properties of workpiece on PMEDM process has been studied. Materials with distinct thermoelectric property, namely Mild Steel and Aluminium are taken as workpiece with Alumina as additive powder for the PMEDM process. Experiments have been conducted with Taguchi L9 Orthogonal Array (OA) with Material Removal Rate (MRR) and Tool Wear Index (TWI) as responses. Gap current, duty cycle and flow rate of powder mixed dielectric liquid have been taken as process parameters at 3 levels with circular copper rod of 12 mm diameter as tool electrode. Determination of the influence of properties of the workpiece on the machinability has been performed using a custom made PMEDM setup. ANOVA and main effect plot of data means for the aforementioned conditions have been analysed. The results are noteworthy with significant influence of the properties of the workpiece on the machinability of PMEDM process.

Semi-empirical modeling and optimization of process parameters on overcut during MFAPM-EDM of Al6061 alloy

“…OC tends to rise on increasing M F from 0.15 to 0.45 T as illustrated in Supplementary Fig. 7 20 comprises of both negative and positive ions which under the influence of Lorentz force changes path of ions and causing more collusions between the ions. Due to this temperature in plasma channel increases which expand the channel causing enlargement in OC.…”

“…Results obtained revealed power concentration have significant effect at higher current. Jeavudeen et al 20 during EDM of mild steel and aluminium with addition of fine alumina powder in dielectric witnessed increase in MRR and tool wear index. Patel and Pradhan 21 analysed the influence of process parameters on surface roughness during EDM of Al 6061 alloy SiC powder mixed in dielectric.…”

Multi-response optimization of PMEDM on Inconel 718 using hybrid T-GRA, TOPSIS, and ANN model

“…Based on Hadi et al [22], it was reported that experiments were conducted with 3 different tools, namely copper, graphite, and copper-graphite, on MONEL 400, and it was found that the copper-graphite tool gave optimal results in terms of MRR and Ra. Jeavudeen et al [23] investigated the effect of three process parameters (gap duty, duty cycle, and flow rate of PM) with aluminum and mild steel (workpiece) by using copper (12 mm dia) as an electrode. They observed that the parameters increase showed the MRR rise (17.52%) in Aluminum and TWI low (4.08%) in mild steel using L9 OA design.…”

Enhancement of machinability of titanium alloy in the Eductor based PMEDM process

“…Various researchers have observed that the performance of PMEDM in terms of machinability has been enhanced by the addition of additive powders with distinct thermo-electrical properties, and at different particle sizes, concentrations, densities etc., [14][15][16]. Also the thermo-electrical property of the workpiece materials do affects the machinability of the materials [17].…”