ANTIRUST PROTECTION OF HEAT-RESISTANT STEELS AND ALLOYS Russian patent published in 2012 - IPC B23H5/00 C25F3/24 

FIELD: process engineering.

SUBSTANCE: invention relates to electrochemistry and may be used in power production, construction, chemical and other industries. Proposed method comprises electrochemical machining with plotting the anode polarisation curve. Note here that limiting current area is defined on said curve. Electrochemical machining is carried out in water solution of electrolyte 15 %-NaNO₃ at 10-12 V, pulse current density of 150 A/cm², pulse duration of 1-5 ms, electrolyte pressure of 0.4-0.6 MPa, pulse frequency of 40-50 Hz, electrolyte temperature of 20-25°C for 10-20 s, and accompanied by electrochemical finishing in sulfur-phosphorus electrolyte with polishing effects for 30-50 s at 25-35°C.

EFFECT: higher rust resistance and surface quality.

3 tbl, 1 dwg, 1 ex