Experimental Investigation on the Effect of EDM Wire Cut Parameters on the Formation of Cr<sub>23</sub>C<sub>6</sub> in AISI 316 Steel

Abstract

Wirecut Electrical Discharge Machining (WEDM) is a manufacturing process typically used to manufacture the machinery components in marine application with complex and challenging shapes and profiles. This study aims to investigate the effect of the EDM wire cut parameters on AISI 316 steel by analyzing the formation of Cr23C6. Cr23C6 can be formed in the grain boundary if the stainless steel is sensitized to a high temperature for too long. This compound becomes susceptible to intergranular corrosion than can reduce structural strength. The formation of Cr23C6 is of interest because this compound becomes vulnerable to intergranular corrosion than can reduce structural strength. The experimental variables in this study are pulse on time (i.e., 8 μs and 12 μs), servo voltage (i.e., 20 V and 30 V), and wire feed (i.e., 5 mm/min and 9 mm/min). The 0.2 mm brass wire is used during the EDM process. The result is then analyzed by surface roughness test, scanning electron microscope (SEM), and Energy-dispersive X-ray spectroscopy (EDS). As a result, the highest and lowest surface roughness values are 2.526 μm 1.771 μm, respectively. SEM results are seen in the pores of holes (craters) and fractures (microcracks). The result of EDS is the additions of elements Carbon (C) and copper (Cu), Oxygen (O). Increased carbon Chrom in HAZ sections allows for corrosion of grain limits.