Role of geometrically necessary dislocations on the superior damping capacity and high strength-ductility of 5083Al/SUS405 laminated heterostructure composites

The laminated heterostructure composite design was implemented on 5083Al alloy. Through the process of vacuum hot pressing (HP state) followed by cold rolling and annealing (CRA state), the 5083Al/SUS405 laminated heterostructure composites (LHCs) were fabricated. The LHCs exhibit excellent combination of strengthductility and damping capacity. The damping in the LHCs originates from the combined effects of dislocation, interface and ferromagnetic damping mechanisms. Compared to 5083Al alloy, the LHCs exhibit higher dislocation damping at relatively high strain amplitudes (epsilon > 0.01 %), especially for the CRA state LHC with higher density of geometrically necessary dislocations (GNDs). This suggests that GNDs not only enhance strengthductility through the hetero-deformation induced (HDI) hardening effect, but also contribute to dislocation damping in the LHCs.