SiO2 Nanoparticles-Containing Slippery-Liquid Infused Porous Surface for Corrosion and Wear Resistance of AZ31 Mg Alloy

A slippery liquid-infused porous surface (SLIPS) was developed, based on MgAl-layered double hydroxide (LDH), in order to improve the corrosion and wear resistance of AZ31 Mg alloys. In particular, different concentrations of SiO2 nanoparticles were incorporated into the silicone oil to further ameliorate the performances of Mg alloys, which can effectively seal the nanopores constructed by MgAl-LDH. With increasing SiO2 nanoparticle concentration, the nanosheet microstructure of MgAl-LDH was gradually covered by the hierarchical structure of SiO2 nanoparticles. The formed composite SiO2-SLIPSs exhibited good surface hydrophobicity and superior corrosion and wear resistance. When the concentration of SiO2 nanoparticle was 10 mg mL−1, the composite SLIPS showed the best performances, with the lowest corrosion current density of 2.43 × 10-10 A cm−2 and wear volume of 0.041 mm3. The developed composite SLIPSs could find wide applications in effective corrosion and wear protection of Mg alloys in industry.