Performance of Modified Nano-SiO2 Composite Phosphating Coating on the Surface of Steel

Abstract

In order to enhance the corrosion resistance and the quality of the phosphating film, nano-SiO2 was used in the phosphating solution.The structure and properties of the phosphating film were evaluated by SEM, electrochemistry, cupric sulfate drop corrosion test and film thickness measurement.The results show that the thickness of the phosphating film increases with the increase of nano-SiO2 content. The nano-SiO2 modified with vinyl triethoxy silane possessed good dispersibility in the phosphating solution, the phosphating solution with the addition of modified nano-SiO2 could greatly improve the corrosion resistance of the phosphating film.