Comparison of machinability of nickel alloys using WEDM

Heat resistance, heat stableness and corrosion resistance are properties that predispose nickel superalloys such as Inconel 625, Mar-M247, Nimonic C 263 and B1914 to a very wide range of applications. Due to their mechanical properties, their machinability by conventional technologies is relatively difficult, so wire electrical discharge machining (WEDM) is widely used, where only one condition is placed on the material being machined, which is at least minimal electrical conductivity. Despite the fact that the main element of which these superalloys are always composed is nickel, their machinability by WEDM is quite different. For this reason, an extensive study comparing the machinability of the four above-mentioned nickel superalloys using WEDM was performed, examining the effect of setting the machine parameters on the cutting speed as well as on the quality of the surface and subsurface layer. It was found out that the cutting speed is different for individual materials with the same set of machine parameters and so that it is possible to significantly increase the quality of the machined surface for individual materials.