Method for preparing corrosion-protection composite coating for the steel metalwork

Abstract

The invention relates to an anticorrosion composite coat for steel metal fastener used in the marine environment, the structure of the composite coat consists of a bottom layer and a surface layer, wherein the bottom layer is coated with lamellar metal zinc dust and lamellar metal aluminum powder which are adhered by adhesive and mixed together, the surface layer is coated with metal aluminum power and reshaping epoxy resin which are mixed together. The invention includes the procedures as follows: the lamellar metal zinc dust and the lamellar metal aluminum power are mixed, and then are added into the inorganic aquosity splicing agent to be stirred and mixed uniformly, and then are soaked into and coated on the anticorrosive metal steel pieces, then are processed by baking and sintering and solidifying to achieve the first step for coating the bottom layer, then the coating and solidifying process is repeated to achieve the second step for coating the bottom layer; additionally, the lamellar aluminum power and the reshaping epoxy resin are mixed to be the organism epoxy aluminium rich paint, the formed bottom layer is made into the surface layer by the different parameter and the same step of the first step of the bottom layer, the method of the invention is of high causticity and strong protection, thereby the base body of the steel fastener can be protected, and the invention is of good abradability, beautiful appearance and ideal decoration.

Description

Technical field: [0001] The invention relates to a metal surface anti-corrosion coating technology, in particular to an anti-corrosion composite coating for steel metal fasteners or connectors used in marine environments. Background technique: [0002] At present, the anti-corrosion measures for steel metal fasteners or connectors used in the marine environment at home and abroad mainly include electroplating cadmium, electrogalvanizing, hot-dip galvanizing and other technologies. Due to the toxicity of cadmium, the susceptibility to hydrogen embrittlement of electroplating, the aging performance of electroplated zinc passivation film at high temperature, and the insufficient corrosion resistance of hot galvanizing, the above-mentioned technologies cannot meet the growing demand for marine environment. Anti-corrosion requirements using steel metal fasteners. Therefore, the research of new technologies to replace the traditional anti-corrosion coating and coating technology ...

AI Technical Summary

Problems solved by technology

[0004] Although the above-mentioned zinc-chromium coatings have good corrosion resistance in ordinary atmospheric environments, it is difficult to meet the requirements for use in water environments or highly corrosive marine environments, because an important factor for the high corrosion resistance of such coatings is The reason is that the trace amount of soluble hexavalent chromium contained in the coating can provide repassivation ability and self-healing effect for the coating. It will be dissolved from the coating, and the anti-corrosion performance of the coating will be greatly reduced after being separated from the coating, and it will cause water pollution when it enters the water environment.

[0005] To sum up, it is still difficult to find an ideal technical solution to solve the anticorrosion problem of metal and steel materials in the marine water environment. The existing methods have shortcomings such as short anticorrosion life, high anticorrosion environment requirements, and complicated equipment. The use of zinc-chrome coatings in highly corrosive environments has the problem of water pollution