Abstract <p>A multilayered hybrid Al1050/AZ31/Al1050 alloy was fabricated by cross-accumulative roll bonding (CARB) up to 5 cycles at 400&#xa0;°C. Microstructure, anelastic, and mechanical properties were characterized using scanning electron microscopy (SEM), internal friction (IF) measurements, and tensile tests, respectively. The thickness of AZ31 layers of the initial sample gradually loses its continuity in the form of localized necking and fragmentation and reduces to less than 150&#xa0;µm after the fifth cycle and, contrarily, that of the Al1050 layer increases. Hot CARB processing causes an enhanced formation of intermetallic compounds. For almost all the cycles, apart from <i>N</i> = 1, the ultimate tensile strength of the sandwich measured in the transverse direction is comparable to that of the rolling direction. A maximum value of 182&#xa0;MPa is achieved after one cycle in the transverse direction and a ductility of 9% is attained, which is close to the maximum values reported in the literature. An investigation of the tensile fracture of surfaces suggests that CARB processing favors ductile failure in Al1050 layers and brittle fracture in AZ31. IF tests highlighted the recrystallization process and grain boundary relaxation in the samples. In both layers, the recrystallization mechanism was of the discontinuous type. Superior mechanical stability of the multilayered hybrid Al1050/AZ31/Al1050 alloy compared to ARB-processed was evidenced. Owing to a specific research gap regarding the damping behavior and internal friction (IF) of CARB-processed Al/Mg composites, the key findings of the present study consist of the original IF analysis revealing recrystallization and GB relaxation kinetics in such a system. The faster relaxation time (<i>τ</i>₀ ≈ 10⁻16&#xa0;s) compared with the IF background plays in favor of an atomic (not dislocation) mechanism of GB relaxation.</p> Graphical Abstract <p></p>