Microstructure and Microhardness Characteristics of TiC–TiN Ceramics Coating by TIG Process on Mild Steel

Abstract

In this work, an experimental fabrication of Titanium Carbide–Titanium Nitride (TiC–TiN) ceramics coating by tungsten inert gas (TIG) coating process on commercial mild steel was extensively carried out to improve surface hardness of the substrate. The thickness of preplaced layer was around 1 mm. The TIG heat source was employed with different current such as 100 A, 110 A, 120 A, and 130 A, voltage and scanning speed were fixed 25 V and 2.60 mm/s, respectively. The FESEM results were revealed that coating employed successfully and microstructure was uniformly distributed in form of lamellar structure. Microhardness analysis across the cross section was detected significantly increments, their values were recorded that the hardness value increased by 3.38–3.82 times higher than that of the substrate hardness. Maximum hardness was recorded 1245.5 HV0.1 whereas hardness value of the substrate was 250 HV0.1.