Hliníkzinek

Hliníkzinek, often referred to as aluminum-zinc alloy coating or Galvalume in some regions, is a type of protective metallic coating applied to steel. It is primarily composed of aluminum (approximately 55%) and zinc (approximately 45%), with a small addition of silicon. This specific composition provides a unique combination of corrosion resistance and sacrificial protection.

The aluminum in the coating offers excellent barrier protection, forming a stable oxide layer that shields the underlying steel from the environment. The zinc component, on the other hand, provides galvanic or sacrificial protection. Even if the coating is scratched and the steel is exposed, the more electronegative zinc will corrode preferentially, protecting the steel from rust. This dual-action mechanism makes hliníkzinek coatings highly effective in extending the service life of steel products, particularly in outdoor and corrosive environments.

Hliníkzinek coatings are commonly applied to steel sheet used in roofing, wall cladding, and other architectural applications. They are also found in some automotive parts, appliances, and general industrial uses where durability and resistance to weathering are important. The coating is typically applied via a continuous hot-dip process, where the steel strip is passed through a bath of molten aluminum-zinc alloy. The resulting coating has a distinctive spangled or crystalline appearance. Its performance characteristics make it a popular choice for applications requiring long-term corrosion protection.