Phosphorus-free conversion (steel floor)

Phosphorus-free conversion used in steel flooring is a new type of surface treatment technology, which is mainly used to replace the traditional phosphorus-containing conversion treatment process. It has the advantages of environmental protection and high efficiency. The following is an introduction from the aspects of principle, treatment process, advantages and application:

principle

Phosphorus-free conversion technology is usually based on phosphorus-free compounds such as zirconium salts and titanium salts, which form a conversion film on the steel surface through chemical reactions. Taking zirconium salts as an example, the zirconium ions in the solution will exchange with the iron ions on the steel surface, and other components in the solution will react with groups such as hydroxyl groups on the steel surface to form a composite conversion film composed of zirconium oxides, hydroxides and organic polymers on the steel surface. This film can improve the corrosion resistance, wear resistance and adhesion of the steel surface, providing a good foundation for subsequent coating and other processes.

Processing Flow

Surface pretreatment: First, the surface of the steel floor needs to be cleaned to remove impurities such as oil, dust, rust, etc. to ensure that the conversion film can be well combined with the steel surface. Chemical agents such as degreasing agents and rust removers can be used for treatment, or physical methods such as mechanical polishing can be used.

Phosphorus-free conversion treatment: The pre-treated steel floor is immersed in phosphorus-free conversion liquid, or the conversion liquid is evenly covered on the surface of the steel floor by spraying. Under certain temperature and time conditions, the conversion liquid reacts chemically with the steel surface to form a conversion film. The concentration, temperature, treatment time and other parameters of the conversion liquid need to be optimized and adjusted according to the specific material and process requirements.

Post-treatment: After the conversion treatment is completed, the steel floor needs to be cleaned to remove the conversion liquid and impurities remaining on the surface. It can then be dried to facilitate subsequent painting or other processing steps. In some cases, sealing treatment may also be required to further improve the corrosion resistance and water resistance of the conversion film.

advantage

Good environmental performance: Traditional phosphorus-containing conversion treatment processes will produce phosphorus-containing wastewater, causing environmental pollution. However, phosphorus-free conversion technology does not use phosphorus-containing compounds, avoids phosphorus emissions, meets environmental protection requirements, and helps reduce environmental problems such as eutrophication of water bodies.

Strong corrosion resistance: Phosphorus-free conversion film has good corrosion resistance, which can effectively isolate the steel surface from the contact with corrosive media such as oxygen and moisture in the external environment, and slow down the corrosion rate of steel. Steel floors treated with phosphorus-free conversion can maintain good surface quality and performance during long-term use.

High Adhesion: The phosphorus-free conversion film has a strong bond with the steel surface, which can provide a good adhesion foundation for subsequent coatings, significantly improving the adhesion between the coating and the steel surface. This helps to improve the durability and service life of the coating and reduce the occurrence of problems such as coating shedding.

High treatment efficiency: The phosphorus-free conversion treatment process is relatively simple and the treatment time is short. The surface treatment of the steel floor can be completed in a short time, which improves production efficiency. At the same time, the phosphorus-free conversion liquid has good stability and long service life, which can reduce production costs.