METHOD FOR DIFFUSION HARDENING OF STEEL PARTS Russian patent published in 2016 - IPC B22D19/00 C23C12/00 C21D1/78 

FIELD: technological processes.

SUBSTANCE: invention relates to chemical-thermal treatment of metals and can be used for hardening of parts of machines and tools in machine building, metallurgy, chemical, construction and other industries. Coating is diluted in water to paste state, and then applied on part surface. First layer of coating is applied on part surface with thickness of 0.1-0.2 mm, containing, wt%: titanium 50-75, iron is rest. Second layer of coating containing, wt%: titanium diboride 20-25, boron carbide 70-75, sodium fluoride 2-3, potassium iodide 2-3, is applied with thickness of 3-5 mm. Then, part with two-layer coating is dried in air unless solid crust, heated in heating furnace to temperature of 900-1,150 °C and kept at this temperature for 0.5-4.0. Upon completion of part holding workpiece is annealed, and low-temperature tempering is performed at temperature of 180-200 °C for 2 hours.

EFFECT: increased resistance and service life of steel parts and energy efficiency of hardening process.

1 cl, 1 tbl, 1 ex