An electrolytic passivation solution for stainless steel cookware and its passivation treatment process

Abstract

An electrolytic passivation solution for stainless steel cookware is prepared from, by mass, 50%-70% of a concentrated phosphoric acid solution and 30%-50% of a composite additive. The composite additive is prepared by mixing chlorine alkyl pyridine, benzoic acid, hydroquinone, sulfosalicylic acid and water according to the mass ratio of 2:1:1:3:3. Correspondingly, the invention further provides a passivation technique of the electrolytic passivation solution. The stainless steel cookware passivated through the electrolytic passivation technique has the advantages that the internal color and luster are consistent with the external color and luster, the surface of the cookware is clean and bright, the salt-spray corrosion resistance is high, and the high-temperature color change resistance is greatly improved; meanwhile, the electrolytic passivation technique has the advantages that the technique is simple, the production efficiency is high, and the passivation time is shortened by one time or over.

Description

technical field [0001] The invention relates to the technical field of stainless steel surface treatment, in particular to an electrolytic passivation solution for stainless steel cookware and a passivation treatment process thereof. After passivation by the electrolytic passivation solution, the high-temperature discoloration resistance of the stainless steel cookware is greatly improved. Background technique [0002] In order to improve the service life of stainless steel cookware and give full play to its due practicability, stainless steel cookware must be mechanically rough polished after forming and then undergo electrochemical electrolytic passivation treatment to improve the corrosion resistance of stainless steel and further achieve electrolysis. Fine polished effect. In the traditional process, the electrolytic passivation solution is often formed in a passivation solution composed of sulfuric acid, phosphoric acid, nitric acid, dichromate and other strong oxidizin...

AI Technical Summary

Problems solved by technology

In the traditional process, the electrolytic passivation solution is often formed in a passivation solution composed of sulfuric acid, phosphoric acid, nitric acid, dichromate and other strong oxidizing substances to form a passivation film. The quality of the passivation film directly affects If the passivation film is incomplete or defective, the stainless steel will still be corroded after passivation, reducing the corrosion resistance of the stainless steel workpiece.

[0003] For stainless steel cookware, in the process of mechanical polishing and electrochemical passivation based on sulfuric acid, phosphoric acid, nitric acid, and dichromate, the inhomogeneity and microsegregation of the chemical composition of the material will be affected. Very sensitive, different metallurgical states, different materials, inhomogeneity of metal grain size structure and rolling forming traces, etc., will have a negative impact on the smooth effect of the cookware surface, resulting in dull surface after passivation, color effect Not ideal, at the same time, the heavy metal ions contained in the electrolytic passivation solution will pollute the environment and affect health

In addition, after the workpiece is passivated in the existing passivation solution, there will be corrosion spots on the surface. More importantly, in the high-temperature overshoot of stainless steel cookware, a dark film will quickly form on the surface, which is the original The high-temperature discoloration mentioned in the invention affects the aesthetics of cookware