New Method for Nitrocarburizing Steel Parts

There is proposed a new process for nitrocarburizing steel parts by the method of electrospark alloying (ESA), which includes applying a paste-like nitrogenous component to the surface of the part and, without waiting for it to dry, processing it with the use of the ESA method by a graphite electrode-tool. In this case, with an increase in the discharge energy of 0.13 to 3.4 J, the following, respectively, increases: the thickness of the “white” layer from 10 to 120 microns; the microhardness of the surface layer of 6665 to 9932 MPa; the surface roughness (Ra) of 0.8 to 4.7 microns, and the coating uniformity of 80 to 100%. At all discharge energies, most of the amounts of carbon and nitrogen are closer to the surface and they have been decreasing while deepening. With an increase in the discharge energy of 0.13 to 3.4 J, the depths of the diffusion zones of carbon and nitrogen, respectively, increase of 20 to 45 and of 20 to 55 microns.