Surface Modification of AISI 1018 Low Carbon Steel by Duplex Treatment of Nitrocarburizing and Post-Oxidation

The duplex treatment combining the salt bath nitrocarburizing with post-oxidation technique provides an excellent technique for achieving improved hardness, wear and corrosion resistance of the surface of various steels. Arcor^® is a merger of Sursulf and a post-oxidation process (Oxynit). In the present research effects of the duplex treatment (nitrocarburizing and post-oxidation) on the surface morphology of AISI 1018 low carbon steel are reported. Observations revealed that by increasing the holding time a considerable improvement in mechanical properties occured. Optical microscopy investigations revealed compound and diffusion zones on the steel surface with approx. 24 μm thick compounds and oxide layer. Furthermore, a significant decrease in specific wear rate has been observed due to the compact and uniform compound layer.