Low temperature nitriding of medium carbon steel

The authors present the results of nitriding of medium carbon steel at a low temperature of 573 K by using the surface-alternating current nanocrystalline treatment (SACNT), which is much lower than conventional nitriding temperature (about 773 K). The SACNT induces electrovalent bond to part by means of the iron ion transgressing, and the surface evolves to ultrafine grain layer. The nanostructured surface layer enhances the nitriding kinetics of pre-treated medium carbon steel. The samples were characterized by metallographic testing (scanning electron microscopy (SEM) and optical microscope (OM)), microhardness tester and X-ray diffraction.