A novel Cu-Gr composite electrode development for electric discharge machining of Inconel 718 alloy

Abstract

Requirement of processes with high productivity leads to the development of new tools and machining technique. One such attempt was made to develop a Copper Composite (CC) tool reinforced with graphite particles through the stir casting route. The CC tool was utilized to machine the Inconel 718 alloy using Electric Discharge Machining (EDM) technique by varying input variables viz tool material, discharge current, pulse on time, pulse off time and gap distance. Brass, Copper, Copper-5% Graphite (CG5), Copper-10% Graphite (CG10), Copper-15% Graphite (CG15) are the various used tool material whereas Material Removal Rate (MRR), Tool Wear Ratio (TWR) and Surface Roughness (R a ) were recorded as responses. The results revealed that using the CG10 and CG15 tools causes arcing and open circuit under some parametric conditions. CG5 offers best MRR and least TWR owing to the bridging effect, high thermal conductivity and lesser density which was suitable for roughing operation whereas brass offers least R a which was recommended for finishing operation. The surface topography was analyzed with the aid of Scanning Electron Microscope (SEM). Micro crack, pock marks, globules and remelted layers are some of the defects observed in surface morphology. The process parameters was optimized using VIKOR technique.

Impact of SiC Particle Incorporated Dielectric Medium on Machining Performance of AA7050/SiC/Al2O3 Hybrid Composites

“…20 The MRR raises with increase in Ton and maximum MRR of 59.87 mg min −1 was recorded for the Ton of 40 s. At higher Ton the generated heat hanged inside the spark gap for extended period of time which increases the rate of material removal. 21 The MRR reduces with increase in weight percentage of the composites, mean MRR of AA7050/2SiC/2Al 2 O 3 hybrid composites were 65.73 mg min −1 and it was reduced to 52.19 mg min −1 when AA7050/8SiC/8Al 2 O 3 were machined with same parametric combination. When machined the composites, owing to the difference in the melting point of matrix and reinforcing particles, the material surrounds the reinforcement gets melted leads to the detachment of particles from the surface.…”

Electric Discharge Machining of AZ91 Magnesium Hybrid Composites under Different Dielectric Mediums

“…e specimens were machined for 10 minutes, and the average value was documented as MRR, TWR, and Ra. e MRR and TWR were calculated using equations ( 1) and (2) [33], which was the ratio of heft difference afore and after machining to the product of machined time and density. e heft of the work piece and tool was determined using electronic weighing equipment with a 0.0001 g precision.…”

Experimental optimization of machining GH4145 by atomizing discharge ablation milling

“…Regarding the exploration and research on EDM processing of difficult to machine materials, many literature studies have been conducted on material properties, structural forms of tool electrodes, and the types of discharge medium. Somu C et al [6] changed the physical and chemical properties of the tool electrode by adding Cr metal material into the copper metal electrode. They achieved higher machining results on Inconel 718 Alloy through EDM.…”