METHOD FOR MANUFACTURING WELDED STRUCTURES FROM THERMALLY NONHARDENABLE ALUMINIUM ALLOYS Russian patent published in 2018 - IPC B23K20/12 C22F1/04 B23K103/10 

FIELD: metallurgy.

SUBSTANCE: equal channel angular pressing of the part blank is carried out along the route of the aircraft in not less than 8 passes with the combination of the heating temperature in the range of 250-500°C according to the condition for obtaining a recrystallized structure of the aluminium alloy of the blank with a volume ratio of recrystallization grains of at least 75%. The isothermal rolling of the resulting blank is then carried out at a temperature not less than the pressing temperature and not exceeding the mentioned temperature by more than 50°C, to produce sheet semi-finished products of a predetermined size. After that, the obtained sheet semi-finished products are joined by friction stir welding. The tool rotation speed and feed rate are selected according to the condition for obtaining a weld joint structure identical to the structure of the aluminium alloy semi-finished product.

EFFECT: increasing operational reliability of welded structures.

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