Strength-isotropy synergy in a rolled Al-Cu-Li alloy through integrated design of recrystallization and aging precipitation

• Rolling process design achieves strength-isotropy synergy in Al-Cu-Li alloy. • Promoted recrystallization optimizes texture and reduces anisotropy. • Cold rolling-induced dislocations enhance aging precipitation and strength. • Quantitative decoupling of strength contributions is performed in aged samples. Cold rolling (CR) strengthens Al-Cu-Li alloys but induces anisotropic deformation textures, creating a strength-isotropy trade-off. To address this, various rolling strategies, including hot rolling (HR), CR, and combined HR + CR with varying HR/CR ratios (1:3–2:1), were designed to regulate the microstructural evolution and mechanical anisotropy in an Al-3.5Cu-1Li alloy. The results demonstrate that the optimized rolling precipitation behavior in HR + CR alloy promotes static recrystallization during the solution treatment via particle-stimulated nucleation mechanism, effectively reducing anisotropy. In addition, the precipitation kinetics could be promoted during the aging process by the CR-induced dislocation, which is conductive to the strength. A decreased HR/CR ratio concurrently optimized recrystallization and aging precipitation. The aged sample with an HR/CR ratio of 1:2 obtained optimal isotropy and comprehensive mechanical properties: rolling direction, YS = 551 MPa, UTS = 583 MPa, EL = 12.0 %; transverse direction, YS = 528 MPa, UTS = 564 MPa, EL = 12.7 %. The optimized alloy demonstrates strength on par with its cold-rolled counterpart, while exhibiting significantly enhanced ductility. Notably, the anisotropy is reduced by over 20 % in YS and 50 % in EL. This strategy offers a viable route to the preparation of isotropic high-strength Al-Li alloys.