WEDM-Cut NiCrMo: A Comparison of Copper and Brass Wires

WEDM (Wire Electrical Discharge Machining) is an advanced manufacturing method based on the principle of chip removal by creating high-frequency electrical sparks between the workpiece and the wire electrode. In this method, the wire electrode does not come into contact with the workpiece; instead, electrical discharge occurs through a very small gap. This method offers contactless processing, high precision and smoothness, control of thermal effects, complex geometry cuts, and the ability to process hard materials with tight tolerances, making it possible to easily process materials such as super alloys, carbides, titanium, Inconel, and NiCrMo. In this study, the cutting of NiCrMo alloy, which is difficult to process due to its high strength and low thermal conductivity, using copper and brass wire electrodes in the WEDM method was investigated. SEM (Scanning Electron Microscope) and EDX (Energy Dispersive X-Ray) analyses of the cut surfaces revealed the formation of micro cracks, voids, globules, craters, and debris on the processed surfaces, as well as electrode residues such as Cu and Zn. It was observed that the average surface roughness values of the surfaces cut using copper and brass wire electrodes were 2.331 µm and 3.919 µm Ra, respectively. It has been determined that copper wire is 40.52% more efficient than brass wire electrodes due to its high conductivity, good thermal diffusion and more stable discharges.