Experimental investigation of magnetic-field-assisted electric discharge machining by silicon-based dielectric of Inconel 706 superalloy

Abstract

Inconel 706 is a nickel–iron-based superalloy having higher mechanical strength along with easiness of fabrication, which makes it suitable for gas turbine disk applications. The current study investigates the hybrid magnetic-field-assisted powder mixed electric discharge machining (MFAPMEDM) process to improve performance in machining Inconel 706. For conducting experiments, an in-house set-up was designed and fabricated. Experiments were conducted according to the Taguchi L9 OA and ANOVA to examine the effect of the peak current (Ip) and pulse duration (P-on/P-off) on the material removal rate (MRR) and surface roughness (Ra) of the machined samples. The quality of the machined surface is assessed using a field emission scanning electron microscope (FESEM), which has revealed the presence of micro-holes, melted debris and micro-globules on the machined specimen surface. The Ra is significantly affected by Ip (49.63%) and P-off (37.12%). Further, Ip has more than 78% contribution to the MRR. Furthermore, a mathematical model has been established to develop the relation between input and output factors.