Environment-friendly aluminum and aluminum alloy surface treatment method

Abstract

The invention relates to an environment-friendly aluminum and aluminum alloy surface treatment method, which comprises the following steps: degreasing treatment is carried out on the aluminum or aluminum alloy: soaking the aluminum or aluminum alloy in degreasing solution for a period of time. Washing treatment: washing the aluminum or aluminum alloy taken out from the degreasing solution with clear water. Pickling treatment: soaking the aluminum or aluminum alloy in pickling solution for a period of time, wherein the pH value of the pickling solution is 0.1-4, and the pickling solution comprises the following components: hydrogen peroxide, ammonium bifluoride, hydrofluoric acid and water. Washing treatment: washing the aluminum or aluminum alloy taken out of the pickling solution with clear water. Passivation treatment: soaking aluminum or aluminum alloy in the passivation solution for a period of time. Washing treatment: washing the aluminum or aluminum alloy taken out from the passivation solution with clear water. Drying treatment. The treatment method has the advantages of simple and convenient procedures; high treatment efficiency and low treatment cost, and greatly reduces the pollution to the environment.

Description

technical field [0001] The invention relates to the field of metal surface treatment, in particular to an environment-friendly aluminum and aluminum alloy surface treatment method. Background technique [0002] Aluminum alloy has low density, high strength, good plasticity and can be processed into various profiles. It has excellent electrical conductivity, thermal conductivity and corrosion resistance. It is the most widely used non-ferrous metal structural material in industry. It is used in aviation, aerospace, It has been widely used in automobile, machinery manufacturing, shipbuilding and chemical industry. With the rapid development of industrial economy, the demand for welded structural parts of aluminum alloy is increasing day by day, so that the research on the weldability of aluminum alloy is also in-depth. At present, aluminum alloy is the most widely used alloy. [0003] In order to improve the corrosion resistance of aluminum and aluminum alloys on the market...

AI Technical Summary

Problems solved by technology

However, a high concentration of sodium hydroxide is needed in the alkali etching process, but high concentration of sodium hydroxide is easy to excessively corrode aluminum and aluminum alloys and affect the yield of products

Moreover, high-concentration nitric acid is often used in the pickling process, but high-concentration nitric acid will produce a large amount of polluting gases such as nitrogen monoxide and nitrogen dioxide, which will pollute the environment.

Images