HIGH-STRENGTH ALUMINIUM ALLOY AND METHOD FOR ITS OBTAINING Russian patent published in 2012 - IPC C22C21/10 C22C21/12 C22C21/08 C22C1/03 

FIELD: metallurgy.

SUBSTANCE: aluminium-based alloy contains the following, wt %: zinc - 6.35 - 8.0, magnesium - 0.5 - 2.5, copper - 0.8 -1.3, iron - 0.02 - 0.25, silicon - 0.01 - 0.20, zirconium - 0.07 - 0.20, manganese - 0.001 - 0.1, chrome - 0.001 - 0.05, titanium - 0.01 - 0.10, boron - 0.0002 -0.008, beryllium - 0.0001 - 0.05, at least one element from potassium, sodium, calcium group in quantity of 0.0001 - 0.01 each, aluminium is the rest; at total content of zinc, magnesium, copper within 8.5-11.0, and that of zirconium, manganese and chrome - within 0.1-0.35. Method involves loading and melting of charge components, flux treatment of molten metal, molten metal purification, further vacuum treatment of molten metal in mixer and casting of ingots; boron is added to molten metal in the form of Al-Ti-Be alloy which is distributed at least one hour before molten metal pouring to mixer along the whole surface area of mixer bottom; at that, mixer is pre-heated to temperature which is by 15-30°C more than molten metal temperature, and vacuum treatment of molten metal in mixer is performed at temperature of 695-720°C, during 45-90 minutes.

EFFECT: invention allows obtaining high-strength aluminium alloys with absence of primary intermetallic compounds, decreased content in them of non-metallic inclusions and dissolved gases, with stable properties and optimum size of grain on basis of standard furnace and process equipment.

2 cl, 3 tbl