FABRICATION OF REINFORCED LAYER ON TREADED SURFACE OF PART FROM ALLOYED STEELS Russian patent published in 2015 - IPC C25F3/24 C23C14/48 

FIELD: process engineering.

SUBSTANCE: invention relates to machine building and can be used for surface hardening of parts with threaded surfaces used, for example, in roller-screw and boll-screw gearings. This process comprises shaping the thread geometry by thread cutting tool and processing by electrolyte-plasma process. Here, part is dipped in electrolyte, 3-8% water solution of ammonia sulphate, to produce vapour-gas shell. Electric discharge is fired between processed part and electrolyte by feed of electric potential to processed part. Note here that electrolyte-plasma polishing of threaded surface is performed at 260-310 V, electrolyte temperature of 70-85°C and current density of 0.20-0.55 A/cm². After electrolyte-plasma processing of threaded surface the part is placed in vacuum chamber fir ion-implant processing.Ionic cleaning by argon ions is performed at 6-8 keV, current density of 100-120 mcA/cm² for 0.2-0.8 hours and ion-implant processing of part surface by ions of ytterbium or nitrogen at 20-35 keV.

EFFECT: higher wear resistance and antifriction properties.

12 cl, 1 ex