The present work attempted to produce thick zirconia coatings formed by micro-arc oxidation as a hydrogen permeation barrier on zirconium hydride alloy. A novel multiphase zirconia coating was achieved, exhibiting superior hydrogen permeation barrier performance. The growth dynamics, formation mechanism, and phase evolution behavior of thick zirconia coatings were explored, and the hydrogen permeation barrier performance was evaluated by means of vacuum dehydrogenation experiment. The hydrogen desorption quantity was monitored by analyzing pressure changes with a quadruple mass spectrometer (QMS). Experimental results show that the multiphase coatings were composed of monoclinic ZrO₂ (m-ZrO₂), tetragonal ZrO₂ (t-ZrO₂), and a trace of cubic ZrO₂ (c-ZrO₂). The coatings were generally divided into a dense and uniform inner, intermediate layer, and a porous top layer. The quantitative analysis indicates an increased amount of m-ZrO₂ toward the coating surface and an increased amount of t-ZrO₂ toward the oxide/metal interface. This novel multiphase thick zirconia coating can noticeably improve hydrogen permeation resistance, and the permeation reduction factor (PRF) value is improved by nearly 13 times compared with bare zirconium hydride. It is demonstrated that hydrogen desorption is retarded to some extent in the presence of thick zirconia coating. Hydrogen desorption of the sample with ceramic coating started at 660 °C, which was apparently higher than that of the sample without coating.

Magnesium alloys, notably AZ31B, hold promise for lightweight structural applications in the aerospace, automotive, and biomedical sectors due to their excellent strength-to-weight ratios. The broad adoption of these alloys, however, is hindered by their inherent susceptibility to corrosion, reducing durability and functional integrity in corrosive environments. This study explores anodic oxidation as a viable surface treatment to improve the corrosion resistance of the AZ31B magnesium alloy. Focusing on the impact of oxidation voltage on the oxide film’s structural and electrochemical properties, we aim to optimize these characteristics to enhance the alloy’s utility and lifespan significantly. Through detailed analysis of surface and cross-sectional morphologies, film thickness, phase composition, and corrosion resistance, we identify an optimal oxidation voltage of 17.5 V that notably improves the oxide film’s density and corrosion resistance. Through this research, we contribute to the ongoing efforts to overcome the corrosion vulnerability of magnesium alloys, thereby unlocking their full potential in contributing to more sustainable and efficient technological advancements.