Effects of pre-sputtered Al interlayer on the atomic layer deposition of Al2O3 films on Mg–10Li–0.5Zn alloy

► Deposition of a dual-layer Al/Al2O3 films on Mg–10Li–0.5Zn substrate using both techniques of magnetron sputtering and atomic layer deposition (ALD). ► Identify the crystal structure, chemical composition, surface morphology of the dual-layer Al/Al2O3 films. ► Clarify the effects of dual-layer Al/Al2O3 films on the corrosion resistance of Mg–Li alloys. In this study, a dual-layer of Al/Al2O3 films was deposited on the Mg–10Li–0.5Zn substrate using both techniques of magnetron sputtering and atomic layer deposition (ALD). The pre-sputtered Al interlayer has a crystalline structure and the ALD-Al2O3 film is amorphous. The Al interlayer could effectively obstruct the diffusion out of Li atoms from the Mg–10Li–0.5Zn substrate during the deposition of ALD-Al2O3 film. The Mg–10Li–0.5Zn specimen with a dual-layer of Al/Al2O3 films exhibits a much better corrosion resistance than those specimens with a single layer of sputtered Al or ALD-Al2O3.