High weather-resistance aluminum alloy chromate-free passivator and preparation method thereof

Abstract

The invention discloses a high weather-resistance aluminum alloy chromate-free passivator. The high weather-resistance aluminum alloy chromate-free passivator comprises the following raw materials of, by weight, 5-10 parts of 30-40% of hexafluorotitanic acid, 5-10 parts of 40-45% of hexafluorozirconic acid, 1-2 parts of sodium fluoride, 1-2 parts of 65-70% of nitric acid, 1-2 parts of benzotriazole, 0.5-1 part of lauric acid polyoxyethylene ester, 0.3-0.5 part of gallate propyl ester, 3-5 parts of 1-hydroxy ethylidene-1,1-diphosphonic acid (HEDP), 50-100 parts of coalescing agents, 1-2 parts of hydroxypropyl methyl cellulose (HPMC), and 800-1000 parts of water. According to the high weather-resistance aluminum alloy chromate-free passivator, the aluminum alloy chromate-free passivator can form a compact thin film which is of a reticular structure on the surface of aluminum alloy; the thin film has excellent strength, toughness, adhesive ability and corrosion resistance; meanwhile, the weather resistance is high, the service life is long, effective protection for a long time can be provided, and environment pollution can be reduced; accordingly, good economic benefits and social benefits are achieved.

Description

technical field [0001] The invention relates to the technical field of aluminum alloy passivation, in particular to a chromium-free passivator for high weather resistance aluminum alloy and a preparation method thereof. Background technique [0002] Aluminum alloys have many excellent properties and are widely used in many fields such as transportation, packaging containers, aerospace, household appliances, machinery manufacturing, building profiles, and electronic communications. However, aluminum alloys have poor corrosion resistance, wear resistance, and hardness, and are easily corroded during use. Therefore, aluminum profiles must undergo effective surface treatment before coating to avoid or reduce corrosion. [0003] As the most commonly used aluminum alloy surface treatment technology, chromate passivation treatment has the advantages of convenient use, low price, good corrosion resistance and decorative performance, but the hexavalent chromium in the treatment solut...

AI Technical Summary

Problems solved by technology

Among them, titanium-zirconium-based passivation technology has the advantages of simple process, good stability and low cost, but its corrosion resistance and adhesion are not as good as chromate passivation treatment, which limits its application.