METHOD FOR ION NITRIDING OF PARTS FROM ALLOYED STEEL Russian patent published in 2022 - IPC C23C8/26 C23C8/02 C23C8/38 C23C14/48 C25F3/24 

FIELD: metallurgy.

SUBSTANCE: invention relates to metallurgy, in particular to methods for chemical-thermal treatment of alloy steel parts, and can be used in mechanical engineering for surface hardening of machine parts, including parts operating in friction pairs, gears and rotors of screw pumps and engines. The method includes activation of the part surface before nitriding, heating the part to the nitriding temperature and holding the part at this temperature until the required thickness of the nitrided layer is formed. At the same time, the activation of the surface of the part is carried out in two stages, at the first stage of activation, the part is polished in the environment of granules made of anion exchangers containing an electrolyte solution, moving the part in the environment of the granules, ensuring contact of the surface of the part with the granules. An electric potential of different sign is applied to the part and to the granules in a pulsed mode with a polarity reversal. The first stage of activation is carried out until the roughness is not lower than Ra = 0.08…0.12 μm, and at the second stage of activation, ion-implantation treatment of the surface of the part is carried out with chromium ions at an ion energy of 20 to 28 keV, an irradiation dose of 1.1⋅10¹⁷ cm^-2 to 1.1⋅10¹⁷ cm^-2.

EFFECT: increasing the wear resistance of the nitrided layer of parts made of alloyed steels.

2 cl, 1 tbl, 2 dwg