Preparation of mechanically stable superhydrophobic materials and protection of Mg alloy by combination of an epoxy coating

Superhydrophobic materials have attracted significant attention for their exceptional surface wettability. However, their short service life limits their application in practical anti-corrosion engineering. Magnesium alloys exhibit numerous unique properties but suffer from poor corrosion resistance. To enable the widespread use of magnesium alloys, it is crucial to develop effective anti-corrosion strategies. In this study, a mechanically stable superhydrophobic material was developed using siloxane-modified SiO₂ combined with an adhesive. Test results showed that the contact angle of this superhydrophobic material reached 160° and demonstrated excellent mechanical stability and antifouling properties. Even after 60 cycles of tape adhesion-peeling tests, the contact angle was remained above 150°. In addition, we used an epoxy resin (EP) coating as a primer and sprayed this superhydrophobic material on its surface to prepare a dual-layer coating for the anti-corrosion of magnesium alloys. The coating retained outstanding anti-corrosion performance after immersion in a 3.5 % NaCl solution for 30 days, with impedance values two orders of magnitude higher than those of the pure EP coating. The combination of superhydrophobic material and EP coating provides durable and effective protection for magnesium alloys. We believe that this method presents a promising approach for designing novel anti-corrosion coatings.