METHOD FOR MANUFACTURING A STRUCTURAL ELEMENT HAVING A VARIABLE THICKNESS FOR AIRCRAFT PRODUCTION

摘要

The invention relates to the method for manufacturing a rolled product of variable thickness made of heat-treatable aluminum alloy in which hot rolling is performed to achieve a variation in thickness of at least 10% lengthwise between the thickest part and the thinnest part; the rolled product of variable thickness obtained undergoes solution heat-treatment and quenching with permanent set of at least 1% in the thickest part before natural or artificial ageing. The products obtained according to the invention exhibit improved mechanical strength of at least 5% in the thinnest part and improved fracture toughness of at least 15% in the thickest part. The products according to the invention are notably useful in the fabrication of aircraft upper or lower wing skins the “buy to fly” ratio and the properties are simultaneously improved.

主权项

1. A method for manufacturing a rolled product of variable thickness made of heat-treatable aluminum alloy, in which
a. a slab made of heat-treatable aluminum alloy is cast, b. optionally, said slab is homogenized, c. said optionally homogenized slab is hot rolled, by achieving a lengthwise thickness variation to obtain a rolled product of variable thickness, having a thicker part and a thinner part, the difference in thickness of which is at least 10%, d. said rolled product of variable thickness is solution heat-treated and quenched, e. said rolled product of variable thickness, thus solution heat-treated and quenched, is stress relieved by controlled stretching, with a permanent set of at least 1% in the thickest part, f. the rolled product so obtained is naturally or artificially aged.