Method of making a structural element for aeronautical construction comprising differential work-hardening

Worked product consisting of a 2XXX alloy in the T3X temper prepared by a hot working step, and at least one working step by cold plastic deformation after the hot working step, wherein at least two zones of said worked product have imposed generalized average plastic deformations, wherein the imposed deformations are different by at least 2%;

• wherein at least two zones Z1 and Z2 have mechanical properties wherein at least one of the following is satisfied
• (i) the difference in the Rp0.2 values measured in the L direction or in the LT direction Rp0.2(Z1)−Rp0.2(Z2) is equal to at least 50 MPa
• (ii) the difference in the Rm values measured in the L direction or in the LT direction Rm(Z1)−Rm(Z2) is equal to at least 20 MPa
• (iii) the difference K1c measured in the L-T direction, K1c(Z1)−K1c(Z2), is equal to at least 5 MPa√m;
• and
• wherein the worked product consisting of a 2XXX alloy in the T3X temper is naturally aged.

Worked product consisting of a 2XXX alloy containing lithium in the T8X temper prepared by a hot working step, and at least one working step by cold plastic deformation after the hot working step, wherein at least two zones of said worked product have imposed generalized average plastic deformations, wherein the imposed deformations are different by at least 2%;

• wherein at least two zones Z1 and Z2 have mechanical properties selected from the group consisting of
• (i) Z1:
• Rm(L)>630 MPa and Z2:
• A(L)(%)>8%
• (ii) Z1:
• Rm(L)>640 MPa and Z2:
• A(L)(%)>7%
• (iii) Z1:
• Rm(L)>630 MPa and Z2 K1c(L-T)>25 MPa√m.