Innovative approach to boosting the chemical stability of AZ31 magnesium alloy using polymer-modified hybrid metal oxides

Abstract

Meeting the demands of complex and advanced applications requires the development of high-performance hybrid materials with unique properties. However, the integration of polymeric frameworks with MgO/WO3 composite layers faces challenges due to the lack of understanding of the formation mechanism and the challenge of determining the impact of self-assembled architecture on anticorrosive properties. In this study, we aimed to enhance the corrosion resistance of the MgO layer produced by plasma electrolysis (PE) of AZ31 Mg alloy by incorporating WO3 with partially phosphorated poly(vinyl alcohol) (PPVA). Two types of porous MgO layers were produced using the PE process with an alkaline-phosphate electrolyte, one with and one without WO3 nanoparticles, which were subsequently immersed in an aqueous solution of PPVA. Incorporating PPVA into the WO3-MgO layer resulted in hybrids being deposited in a fragmented manner, creating a ``laminar reef-like structure'' that sealed most of the structural defects in the layer. The PPVA-sealed WO3-based coating exhibited superior corrosion resistance compared to the other samples. Computational analyses were employed to explore the mechanism underlying the formation of PPVA/WO3 hybrids on the MgO layer. These findings suggest that PPVA-WO3-MgO hybrid coatings can potentially improve corrosion resistance in various fields.

Keywords

• Plasma electrolysis
• Poly(vinyl alcohol)
• Tungsten trioxide
• Sealing
• Corrosion
• DFT