Effect of age-forming on microstructure, mechanical and corrosion properties of a novel Al-Li alloy

The age-forming technology of Al-Li alloy has caused considerable attention in recent years. In this study, the effects of age-forming on microstructure, mechanical and corrosion properties of a novel Al-Li alloy are studied. Results show that age-forming in the novel Al-Li alloy enhances the mechanical properties including strength and elongation, meanwhile, improves the corrosion resistance. The stress during the aging does not change the morphology of the grains, but inhibits the precipitation of θ′ phases, promotes precipitation of T1 phases and reduces the dimension of T1 phases. The orientation effect for the θ′ phases is obvious, while for the T1 phases, this effect is not obvious under the load of 100 MPa. At the same time, age-forming helps to inhibit grain boundary precipitate coarsening and the PFZ widening.