METHOD OF APPLICATION OF MIXED CARBON-NITROGEN PROTECTIVE COATING TO INCREASE CORROSIVE STABILITY OF IRON Russian patent published in 2018 - IPC C23C14/30 C23C14/35 C23C14/48 

FIELD: technological processes.

SUBSTANCE: invention relates to methods for protecting metals from corrosion, in particular to a method for applying a protective coating to an iron substrate, and can be used for the manufacture of products and parts operating in corrosive environments for the oil, gas, chemical and other industries. Magnetron sputtering on the iron of the carbon layer is carried out. Resulting carbon layer is bombarded with singly charged nitrogen ions to a nitrogen penetration depth of 3–5 nm below the carbon layer – iron interface to form carbonitrides at the indicated depth. Magnetron sputtering of the carbon layer is performed using graphite targets at a direct current with a substrate temperature of 180–230 °C. Bombardment by nitrogen ions N⁺ is performed with an energy of 10–30 keV with doses of D=5·10¹⁶–10¹⁷ ion/cm² vertically to the surface of the target in a pulse-periodic mode with a pulse duration of 0.5–1 ms, with a repetition rate of 80–120 Hz.

EFFECT: as a result, corrosion resistance and hardness of the iron surfaces treated in this way are obtained.

1 cl, 6 dwg