Why passivation is important for aluminum pigments

2024-07-27

Passivation is a process whereby a metal is treated or coated to reduce its surface chemical reactivity. A “passive” substrate is less susceptible to environmental impact or corrosion than other substrates. During the passivation process, the substrate chemically reacts to form an outer layer of protective material.

Passivation is widely used in many industries, but is particularly prevalent in the automotive industry. In the automotive industry, aluminum pigments are used in coatings to improve the appearance of the vehicle. The use of aluminum pigments in this market segment continues to expand. The global aluminum powder, aluminum paste, and aluminum flake market has a compound annual growth rate (CAGR) of 6%.

So what are the main reasons why passivation is important for aluminum pigments:

Enhanced corrosion resistance: Aluminum pigments are often treated during the production process to enhance their corrosion resistance. Passivation treatment forms a strong oxide surface layer that protects the aluminum pigment from further oxidation or corrosion in air, water, or chemicals, extending its service life.

Improve appearance quality: The surface of aluminum pigment after passivation treatment is smoother and more uniform, without obvious oxidation spots or stains, which can ensure its elegant appearance and consistent color after being made into pigment.

Improve adhesion: Passivation treatment can increase the roughness and surface energy of aluminum pigment surface, and improve its adhesion with other materials (such as coatings, plastics, etc.). This ensures the stability and reliability of the pigment during coating or mixing.

Environmental friendliness: Passivation treatment usually adopts environmentally friendly chemical methods, avoiding the emission of harmful waste or pollutants that may be generated in traditional chemical treatment. This meets modern environmental protection requirements and helps to reduce the environmental impact of the production process.

Improve process performance: Aluminum pigments after passivation treatment are easier to operate and control during processing and manufacturing, and their surface treatment is not easy to produce dust, residue or other adverse effects, which is conducive to improving production efficiency and product quality.

Comply with industry standards and requirements: Many industries (such as automobiles, construction, aerospace, etc.) require that the materials used meet specific standards and specifications. Passivation treatment is one of the key steps to ensure that aluminum pigments can meet these standard requirements.

Passivation treatment is crucial for aluminum pigment paste, which not only improves their corrosion resistance and appearance quality, but also improves their process performance and environmental friendliness, ensuring their stability and reliability in various application fields.