METAL SHEET WITH ZnAlMg COATING WITH SPECIAL MICROSTRUCTURE AND CORRESPONDING METHOD OF PRODUCTION Russian patent published in 2017 - IPC C23C2/06 C23C2/26 C23C2/28 C23C28/00 

FIELD: metallurgy.

SUBSTANCE: invention relates to a metal sheet (1) comprising a substrate (3) with a metal coating (7) applied to at least one of its surfaces (5), the corrosion resistance of which increases during colouring. The metal coating (7) contains Al and Mg and the rest - Zn, unavoidable impurities and optionally one or more additional elements selected from Si, Sb, Pb, Ti, Ca, Mn, Sn, La, Ce, Cr or Bi. The coating (7) has a microstructure containing the plate matrix Zn/Al/MgZn₂ with a ternary eutectic, as well as Zn dendrites with accumulated surface content at the outer surface (21) of the coating (7) in the untreated state equal to zero or less than or equal to 5.0%, spangles of the binary eutectic Zn/MgZn₂ with the accumulated surface content at the outer surface (21) of the coating (7) in the untreated state equal to zero or less than or equal to 15.0%, dendrites of the binary eutectic Zn/Al with accumulated surface content at the outer surface (21) of the metal coating (7) in the untreated state equal to zero or less than 1.0%, the islets MgZn₂ with the accumulated surface content at the outer surface (21) of the coating (7) in the untreated state equal to zero or less than 1.0%.

EFFECT: improving the characteristics of the sheet.

15 cl, 6 dwg, 1 tbl