METHOD OF PRODUCING STEEL SHEET WITH METAL COATING Russian patent published in 2019 - IPC C21D8/04 C21D1/76 C21D9/50 C23C2/00 

FIELD: metallurgy.

SUBSTANCE: performing continuous annealing in furnace with atmosphere of inert gas and H₂, including preliminary heating to 200–350 °C in atmosphere A1 with dew point below -20 °C at pressure P1, having H₂ less than 3.0 vol%, further heating to 600–1,000 °C in atmosphere A2 with dew point below -40 °C at pressure P2 above P1, having H₂ less than 0.5 vol%, holding in atmosphere A3, having H₂ less than 3.0 vol%, cooling to 400–800 °C in atmosphere A4 with dew point below -30 °C, having H₂ less than 2.0 vol%, alignment of temperature of edges and sheet centre in atmosphere A5 with dew point below -30 °C, having H₂ less than 2.0 vol%, and sheet movement by means of device with hot tension rollers in metal melt bath for application of coating in atmosphere A5 with dew point below -30 °C, having H₂ less than 2.0 vol%, at that, atmosphere A2 is continuously removed in the direction of pre-heating and holding furnace section, and atmospheres A1, A3, A5 and A6 are released periodically or continuously through furnace openings.

EFFECT: improved adhesion of coating with steel sheet.

24 cl, 1 dwg, 1 tbl