A process for fabricating a worked product or a monolithic multi-functional structural element comprising aluminium alloy includes a hot working step and at least one transformation step by cold plastic deformation after the hot transformation step. At least two zones of the structural element have imposed generalized average plastic deformations and the imposed deformations are different by at least 2%. Structural elements can be fabricated, particularly for aeronautical construction, with properties that are variable while their geometric characteristics are identical to those of existing components. The process is economic and controllable, and properties can be varied for parts not requiring any artificial ageing.