METHOD OF COMBINED SURFACE HARDENING Russian patent published in 2014 - IPC B24B39/00 

FIELD: process engineering.

SUBSTANCE: invention relates to surface finishing of parts. Electric current pulses with pulse power density of 700-3000 J/mm² are gated to the point of contact between forming tool and part to make said forming tool press against part surface for plastic deformation and hardening of surface layer. Plastic deformation is effected by subjecting the forming tool to ultrasound oscillations at the frequency of 20-25 kHz and amplitude that ensure development of residual compression stress of -60 MPa to -10 MPa to the depth of part surface hardened layer of up to 200 mcm.

EFFECT: higher fatigue strength and wear resistance of surface layer.

2 dwg, 1 tbl, 1 ex