METHOD OF LOCAL MATERIAL TREATMENT WITH EFFECT OF HOLLOW CATHODE DURING IONIC NITRIDING Russian patent published in 2014 - IPC C23C8/36 

FIELD: machine building.

SUBSTANCE: method of steel part nitriding in plasma of glow discharge includes the cathode spraying, vacuum heating in plasma of the glow discharge comprising of mixture of nitrogen-containing and inert gases with creation of areas with different steel structure. The transition area between areas with different structures has a microheterogeneous structure with gradual transition from one type into another. The heterogeneous structure is formed in form of the macroheterogeneous steel structure using the perforated screen with holes diameter d, at that d > 4 l, where l is thickness of cathode layer, and closely fitting to the treated part, and the screen to ensure effect of the hollow cathode closely fitting to the perforated screen to ensure the possibility to obtain on the surface areas nitrided in the glow discharge and alternating with unnitrided areas.

EFFECT: improvement of contact durability and wear resistance of the strengthened layer due to local treatment and creation of macroheterogeneous material structure.

4 dwg, 1 ex