55. Investigation of Surface Coating on Inconel 718 Alloy with Silicon Carbide Powder

Inconel 718 is a nickel-based superalloy that is extensively used in a broad range of applications such as turbine blades, power generation, petroleum, and nuclear reactor technology due to its good mechanical properties at intermediate and high temperatures. It has been widely used because of its high plasticity and good corrosion resistance. But poor wear resistance of Inconel 718 limits its usage in some applications. In order to perform surface modification of Inconel 718, several surface treatment methods are used. Hence, Electrical Discharge Alloying was performed on Inconel 718 alloy with silicon carbide powder in a medium of dielectric fluid-like EDM oil using reverse polarity in an EDM machine. The experiments were conducted using orthogonal array of Taguchi L9 technique with the input process parameters like current, pulse on time, and pulse off time. The surface modification is studied by analyzing the surface roughness of the alloyed surface using Mitutoyo SJ-210 roughness tester. The alloyed layer of base material Inconel 718 is characterized by using SEM and EDAX. The experiment shows that pulse on time has a major role than other parameters like peak current and pulse off time.