Stainless steel passivation liquid and passivation technology thereof

Abstract

The invention discloses stainless steel passivation liquid and a passivation technology thereof. The stainless steel passivation liquid comprises, by weight, 40-50 parts of inorganic acid, 5-15 parts of hydrogen peroxide, 8-12 parts of cyclohexanol, 4-8 parts of 2-ethylhexyl epoxystearate, 4-6 parts of acetic anhydride, 2-4 parts of polyethyleneimine, 3-5 parts of carbomer resin, 2-4 parts of a penetrating agent, 1-3 parts of corrosion inhibitor and 10-20 parts of organic filler. The passivation technology of the stainless steel passivation liquid comprises polishing and rust removal, surface oil removal, first-time water washing, sand blasting, acid pickling passivation, second-time water washing and surface drying. The stainless steel passivation liquid is little in perniciousness, good in passivation effect and not prone to generating corrosive damage on a stainless steel product. The passivation technology is simple, operation is easy, the production cost is low, pollution to the environment is weak, and the standard of green and environment friendliness is met.

Description

technical field [0001] The invention relates to the field of stainless steel processing, in particular to a stainless steel passivation solution and a passivation process thereof. Background technique [0002] After stainless steel products are processed, most products need to be pickled and passivated to ensure the corrosion resistance of stainless steel products. [0003] Stainless steel has good corrosion resistance, high temperature oxidation resistance, good low temperature resistance and excellent mechanical and processability, so it is widely used in chemical industry, petroleum, power, nuclear engineering, aerospace, ocean, medicine, light industry, textile and other fields. Corrosion resistance is the most important feature of stainless steel. In addition to the difference in material itself, its performance mainly depends on the quality of the passivation film formed on the surface of stainless steel. If the film is incomplete or defective, stainless steel will st...

AI Technical Summary

Problems solved by technology

The passivation solutions commonly used in pickling passivation methods include nitric acid, sulfuric acid, hydrofluoric acid, etc. Although the passivation effect of this type of passivation solution is good, it is extremely corrosive, easy to pollute and dangerous. It will cause different degrees of corrosion such as pitting corrosion, needle corrosion, intergranular corrosion, and transgranular corrosion on stainless steel parts. Some of these corrosion points are the direct source of material fracture, and some are catalysts for material fracture.

In addition, its danger is manifested in that they can react violently with various substances such as metal powder, calcium carbide, turpentine, etc., and cause an explosion. In addition, nitric acid is easily contacted with combustibles, reducing agents and organic substances such as wood chips, cotton, straw or waste sand. It causes combustion and emits highly toxic brown smoke, which is not only inconvenient to use in stainless steel processing, but also incalculable damage to the human body. Therefore, current research is more on passivation technology based on the premise of environmental protection, safety and simplicity. There is also an urgent need for a safe passivation solution with good passivation effect