METHOD OF STEEL SURFACE HARDENING Russian patent published in 2019 - IPC C23C26/00 C21D1/78 

FIELD: metallurgy.

SUBSTANCE: invention relates to hardening of steel and can be used in agricultural machine building to improve wear resistance of tiller blades. Method of steel surface hardening includes heating of surface by electric arc of reverse polarity using first carbon electrode, movement of electrode along hardened surface and addition of ceramic additives. In addition to movement of the first carbon electrode along the hardened surface, it is moved towards the hardened surface at a rate equal to its wear rate and providing a constant arc gap. Strengthened surface ahead of moving first carbon electrode is heated with electric arc of direct polarity using second carbon electrode to temperature of not less than 800 °C, and ceramic additives are introduced into a pool of molten metal formed in the form of a mixture of powders formed behind the first electrode.

EFFECT: enabling the steel surface hardening with the help of a carbon electrode and an electric arc of reverse polarity, which is steadily burning throughout the hardened surface with constant current and constant arc gap.

7 cl, 1 dwg