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The microstructure, texture, and mechanical properties of as-extruded and cold-rolled Mg–8Li–3Al–2Zn-1Gd-0.2Zr (LAZ832-1Gd-0.2Zr) alloys were investigated with the aim of strengthening the alloy by combining hot extrusion and cold rolling. Cold rolling does not change the phase composition of as-extruded LAZ832-1Gd-0.2Zr alloy, but introduces a larger number of dislocations and twins into alloy matrix. Cold rolling leads to the weakening of the original {0001} basal and {112‾0}-{011‾0} prismatic textures in α-Mg matrix, as well as the α and γ fiber textures in β-Li matrix. But new slip systems that are favorable for cold rolling are activated, resulting in the formation of {033‾8} pyramidal and new prismatic ({112‾0}⟨101‾4⟩ and {101‾0}⟨21‾1‾10⟩) texture components. Cold rolling further strengthens LAZ832-1Gd-0.2Zr alloy on the basis of hot extrusion, mainly through work hardening effect caused by introducing a large number of dislocations into α-Mg matrix. When the rolling reduction is 45%, the yield strength and tensile strength of LAZ832-1Gd-0.2Zr alloy are increased to 269.8 ± 4.0 and 308.6 ± 4.1 MPa, respectively, and the elongation is higher than 15%.

The micro-arc oxidation coatings (MAO) coatings formed on the magnesium (Mg) matrix usually have various porosity in the cross-section due to the uneven thermal stress, resulting in the non-consistent compact density in the external and inner layer. However, the consistency of the compact density in the cross-section is less concerned, and its effect on the surficial anti-corrosion and mechanical properties is still unclear. Herein, we employed the Zirconium Oxide particles as a heat-absorbing agent to tune the temperature gradient and achieved the in situ growth of MAO coatings on Mg alloy with a tunable compact density in the external layer and inner layer separately. It is found that compact density plays a key role in corrosion resistance, while the consistency of compact density along the cross-section is very crucial for the mechanical properties. Increasing the compact density and reducing its gradual difference could significantly enhance both the anti-corrosion and mechanical properties. The effect of the inconsistent compact density on the anti-corrosion property could be weakened by reducing the porosity on the external layer, but the simulation results demonstrate its effect on the mechanical properties would be strengthened due to the stress concentration. MAO coatings with homogeneous and compact structures in the cross-section present superior anti-corrosion properties and excellent mechanical properties.