METHOD OF PROTECTIVE OXIDE COATING FORMING ON STEEL SURFACE IN Pb-Bi MELT Russian patent published in 2016 - IPC C23F11/00 

FIELD: technological processes.

SUBSTANCE: invention relates to protective coatings forming technology on steel surfaces contacting with molten Pb-Bi, and can be used for forming protective coatings on steel surfaces contacting with gas media. Method includes preliminary preparation of unoxidized melt Pb-Bi, heated up to 400-700 °C, with subsequent addition of aluminium to it to concentration, equal to 0.1-1.0 wt %, then parts with steel surface are placed into formed Pb-Bi-Al melt and kept for 15-25 hours. Then parts are removed from melt and placed into oxidized Pb-Bi melt, heated to temperature of 350-650 °C and held for 15 hours.

EFFECT: invention provides creating of protective oxide coating, which enables to improve reactor plants operational characteristics due to increasing of steel parts working temperatures and extension of service life.

3 cl, 2 dwg, 1 ex