| 主权项 |
1. Method of manufacturing a rolled or forged product in which:
(a) a slab of alloy is cast, of composition, as a percentage by weight, Cu: 1.8-2.6 Li: 1.3-1.8 Mg: 0.1-0.5 Mn: 0.1-0.5 and Zr<0.05 or Mn<0.05 and Zr 0.10-0.16 Ag: 0-0.5 Zn<0.20 Ti: 0.01-0.15 Fe: <0.1 Si: ≦0.1 other elements <0.05 each and <0.15 total, the remainder aluminum with a density less than 2.670 g/cm3, (b) said slab is homogenized at 480 to 540° C. for 5 to 60 hours, (c) said slab is hot worked by rolling and/or forging, the hot working conditions being such when the manganese content is 0.1 to 0.5% by weight and the zirconium content is less than 0.05% by weight the final hot working temperature is at least 400° C. or when the manganese content is less than 0.05% by weight and the zirconium content is between 0.10 and 0.16% by weight the final hot working temperature is at the most 400° C. to obtain a rolled and/or forged product having a thickness of between 14 and 100 mm, (d) said product is solution-heat treated at 490 to 530° C. for 15 minutes to 8 hours, (e) quench said product with water, (f) said product undergoes controlled stretching with a permanent deformation of 1 to 6%, (g) said product is artificially aged by heat treatment at 120 to 170° C. for 5 minutes to 100 hours. |
