Corrosion Resistance of Polyelectrolyte/SiO2 Nanoparticles Multilayers on Magnesium Alloy: Effect of Heat Treatment

In this work, we demonstrated a novel approach of corrosion protection based on the fabrication of polyelectrolyte/SiO2 nanoparticles multilayers on magnesium alloys. The original multilayers based merely on electrostatic attraction showed porous morphology and weak anti-corrosion protection for the Mg substrate. However, the heat-treatment process would change the microstructures of the multilayers through the cross-linking between the polyelectrolytes and the capping agents of the nanoparticles, and the barrier effects of the coating could be confirmed by polarization and electrochemical impedance spectroscopy. Thus the heat treatment would be an applicable option for preparing the layer-by-layer assembled anti-corrosive multilayers on biomedical Mg alloys.