It is a new type of environmental protection anti-corrosion coating as a substitute for Dacromet coating. It is composed of flake zinc powder, flake aluminum powder, corrosion inhibitor, binder, deionized water, dispersant and other additives, and coated on the substrate. After drying and sintering process, a layer of coating with good corrosion resistance is formed on the substrate. At present, there are few reports on the change of microstructure and corrosion products of chromium-free dacromet coating before and after sintering. Therefore, the change of microstructure of coating before and after sintering and corrosion was studied to explore the anticorrosion mechanism of coating.