A green low-temperature rapid method for preparing phosphating film

Abstract

The invention discloses a method for environment-friendly, low-temperature and rapid preparing of a phosphating film. The method comprises the steps that firstly, raw material components including, by mass, 5-8 parts of dihydric phosphate, 6-9 parts of nitrate, 0.5-3 parts of phosphoric acid, 0.05-0.5 part of oxidized graphene, 0.1-1 part of stabilizer, 6-10 parts of pH buffering agents and 100-120 parts of water are thrown into a reaction kettle, the temperature is increased to 20-40 DEG C, and after stirring is conducted for 20-60 min, the mixture is discharged out of the kettle; and secondly, a prepared phosphating solution is placed in a phosphating pond, the phosphating temperature is increased to 15-40 DEG C, then a steel test piece is placed in the phosphating pond, treatment is conducted for 2-20 min, airing is conducted, and the phosphating film is obtained. The obtained phosphating film is grey and bright in appearance, has good corrosion resistance and is good in attaching force with paint. The phosphating method is high in phosphating speed and low in phosphating temperature. A film layer is fine in crystal, the phosphating liquid is stable, little sediment exists, no toxicity or harm is generated to people and the environment, and cost is low.

Description

technical field [0001] The invention discloses a phosphating film, in particular relates to a method for quickly preparing a green phosphating film at low temperature, and belongs to the fields of material science and surface technology. Background technique [0002] Before spraying and painting, the surface of the metal must be converted to form a conversion film. The conversion film includes phosphating film, passivation film, organic film, rare earth conversion film and sol silane film, etc. Among them, the preparation of phosphating film is to put the metal parts into the salt solution containing Zn, Ni, Mn, Fe and other specific acid phosphate as the main body, and at the same time add various composite additives, after chemical treatment, on the metal parts A phosphate conversion film with a certain thickness and insoluble in water is formed on the surface. The purpose of phosphating is mainly to provide protection for the base metal and prevent the metal from being ...

AI Technical Summary

Problems solved by technology

[0012] The technical problem to be solved by the present invention is to provide a green method for quickly preparing phosphating film at low temperature, so as to solve the problems of high energy consumption, long processing time and complicated phosphating process in the existing phosphating treatment, which lead to the increase of phosphating cost. , to achieve low-cost preparation of corrosion-resistant, wear-resistant phosphating film, and the phosphating solution used does not contain harmful metal ions such as sodium nitrite and chromium, and the operating temperature is normal temperature, which meets the requirements of energy saving, environmental protection and consumption reduction