Study on anti-corrosion performance of silica fume modified magnesium potassium phosphate cement-based coating on steel

In order to explore the anti-corrosion performance of magnesium potassium phosphate cement (MKPC) coating on steel, and the effect of silica fume with different contents on anti-corrosion ability of MKPC coating, electrochemical tests on the uncoated steel plate sample, MKPC coating sample, and silica fume modified MKPC coating samples were carried out in 3.5% sodium chloride solution. The micromorphology and phase composition of MKPC coating sample and silicon fume modified MKPC coating sample were studied by SEM-EDS and XRD tests, as well as the anti-corrosion mechanism. The results show that MKPC-based anti-corrosion coating has good anti-corrosion effect. After the modification of silica fume, the anti-corrosion ability of MKPC coating is greatly improved, when the content of silica fume is 20% of the mass of the magnesium oxide in the gelling system, the corrosion resistance of the coating is optimal.