ALUMINIUM ALLOY SHEET AND ITS MANUFACTURING METHOD Russian patent published in 2015 - IPC C22C21/06 C22F1/47 

FIELD: metallurgy.

SUBSTANCE: aluminium alloy sheet includes a substrate from an aluminium alloy with a composition containing the following, wt %: magnesium 3.0-4.0, manganese 0.2-0.4, iron 0.1-0.5, copper at least 0.03 - less than 0.10, and silicon less than 0.20; with that, aluminium and inevitable impurities are the rest. Peak concentration in the distribution of copper concentration in the thickness direction in the area at the depth of 15 to 200 nm from the substrate surface from the aluminium alloy is equal to or larger than 0.15 wt %. The substrate from the aluminium alloy has a recrystallised structure with an average grain size of 15 mcm or less.

EFFECT: sheet has high mouldability and chemical conversion treatment ability.

6 cl, 3 dwg, 2 tbl, 6 ex