HOT-CLAD ARTICLE HAVING OXIDE LAYER, METHOD OF ITS PRODUCTION AND USE Russian patent published in 2019 - IPC C23F17/00 

FIELD: technological processes.

SUBSTANCE: invention relates to production of hot-plated items with oxide layer. Method comprises steel making, slab casting, hot rolling of steel sheet having oxide layer, low annealing of hot-rolled steel sheet and hot dip coating application. Low annealing of hot-rolled steel sheet with a layer of iron oxides obtained at a hot rolling stage is carried out in a low-annealing furnace without etching in a reducing gas medium at a reduction temperature, wherein on outer surface of steel substrate of hot-rolled sheet remains residual layer of iron oxides, and the surface layer of iron oxides is reduced to a ferrous metal, forming a layer of reduced iron with thickness of 0.5 to 5 mcm, which is located on the surface of the residual layer of iron oxides. Application of coating on hot-rolled steel sheet with layer of reduced iron is performed by means of plating by means of hot immersion method, at that, hot-clad item having oxide layer is formed. At hot rolling stage outlet temperature makes 1,150–1,250 °C, final rolling temperature is 800–900 °C, winding temperature is 550–650 °C, rolling speed is 8–20 m/sec. At the low annealing step, the reduction temperature is 500–1,000 °C, reduction time is 30–300 sec, and reducing gas is a mixture of H₂ or CO with inert gas, wherein concentration of H₂ or CO is not less than 3 %. Invention covers also version of method of making hot-clad articles and hot-clad article.

EFFECT: invention allows reducing the prime cost and improving corrosion resistance of the product.

20 cl, 5 dwg, 1 tbl, 6 ex