PROCEDURE FOR STRENGTHENING WORKING SURFACE OF TEETH Russian patent published in 2011 - IPC C21D9/32 C23C8/22 C21D1/10 

FIELD: machine building.

SUBSTANCE: according to disclosed invention working surface of teeth is subjected to cementing and quenching with currents of high frequency producing transit layer by depth of quenching exceeding depth of cementing with currents of high frequency. Thus, internal thermal stresses are lowered at transition from basic metal to a strengthened layer. There is produced a layer of hardness lower, than the strengthened layer, but higher, than hardness of basic metal, due to depth of quenching with currents of high frequency (HFC) 1.5-2.0 times exceeding depth of cementation. Cementation is carried out at depth h₁, while successive quenching with the HFC- at depth h₂ with temperature t₂, where 0.16 m≤h₁≤0.24 m, h₁≤h₂≤0.7 m, and Ac₃<t₂<Ac₃ init. Ac₃ - is temperature of cemented layer quenching, Ac₃ init. is quenching temperature of basic metal, t₂ is temperature of heating of the HFC 0.7 m; 0.16 m; 0.24 m are specified values.

EFFECT: increased service life of teeth of gears at upgraded quality and reduced prime cost.

2 cl, 1 dwg