The Optimization of the Coating Process Parameters by Electro-Spark Deposition (ESD) Technique Using Steel/Inconel Couple
Mustafa Safa YILMAZ Kemal Korkmaz ALİ ÇAKIR Cengiz DOGRU
AbstractThe aim of the study is searching for the best parameters for St-37 steel surface by Electro Spark Deposition (ESD) method with using Inconel 718 alloy electrode. ESD process was carried out in different voltages (30-62 volt), different frequents (75-130 Hz) and different atmosphere (in air and in silicon oil pool). For varying electrical and ambient conditions, samples were prepared and their coating thickness (9,30 µm - 14,39 µm) and surface roughness (2,043 µm - 5,891 µm) values were measured. The coating thickness was determined higher in the air experiments. Also, thickness and roughness values were increased with the increased voltage, but there were not certain effect of the frequent on thickness and roughness. In addition, SEM images, linear and local EDX analysis, cross-sectional hardness test and XRD analysis were also obtained. It was detected that all coatings have iron-nickel based alloys and CrFe alloy were found in silicon oil pool experiments. Moreover, the cross-sectional hardness tests presented that the coating is two times harder than the steel substrate. By the SEM experiments, it was determine that coating layer had micro pores and good bonding with substrate.