Aluminium powder mixed rotary electric discharge machining (PMEDM) on Inconel 718

Abstract

The rotary tool is a recent innovation of PMEDM. Aluminium oxide (Al₂O₃) powder with a particle concentration of 0.5–1.5 gm/l was added into the dielectric to study improved machining performance. Inconel 718 was machined using copper–tungsten electrode with tool rotation about 300 rpm. Experiments were designed using Taguchi’s three-level L₁₈ orthogonal array. A mathematical model is developed to correlate the influences of these variables such as Peak current (I_p), Sparking gap (V), Pulse on time, (T_on), duty cycle and slurry concentration on MRR. A mean effect plots are generated to develop correlation between the influences of these variables such as Material Removal Rate, Tool Wear Rate, Surface Roughness and Heat affected zone. Recast layer affect means by Scanning Electron Microscopy (SEM).

Keyword:

• Powder mixed EDM
• Rotary Electrode Tool (RET)
• Material Removal Rate (MRR)
• Tool Wear Rate (TWR)
• Surface Roughness (R_a)
• Hole Depth (HD)
• Scanning Electron Microscopy (SEM)
• Energy-Dispersive X-ray spectroscopy (EDX) analysis

Acknowledgements

The authors wish to thank the management of Charotar University of Science & Technology-Changa for facilitating them with the resources.