A New Anticorrosion Composite Coating Containing Sodium Tungstate/Talcum Powder Inhibitor

A sodium tungstate/talcum powder inhibitor was achieved through making sodium tungstate absorb in the layered channels between talcum powders and then dispersively added into epoxy-resin coating to design a new anticorrosion composite coating with self-healing ability. The anticorrosion performance of the composite coating was studied by electrochemical testing and salt-spray testing. The results show that the composite coating could improve the corrosion resistance of metal substrate. The decrease of Cl^- concentration on the surface of metal substrate because of exchanging with sodium tungstate in the layered channels between talcum powders slowed the corrosion of metal substrate down. And the inhibitor of sodium tungstate released from the composite coating was continuously absorbed on the surface of metal substrate, playing a role in repairing the composite coating.