zinkbelagt

Zinkbelagt, or zinc-coated, refers to metal surfaces that have been covered with zinc to prevent corrosion. The zinc coating protects the underlying metal primarily by acting as a sacrificial anode and by forming a barrier against moisture and oxygen.

There are two common methods: hot-dip galvanizing and electrogalvanizing. Hot-dip galvanizing involves cleaning the steel and immersing it in molten zinc, which creates a metallurgical bond and a relatively thick coating that typically ranges from tens to over a hundred micrometres, depending on steel section and immersion time. Electrogalvanizing deposits zinc by electroplating, producing a thinner, more uniform coating, commonly around 5 to 25 micrometres.

Benefits include cost-effectiveness, wide applicability, and long service life in many environments. The zinc layer protects the base metal both as a barrier and as a sacrificial anode, so protection remains even if the coating is scratched or damaged. The coatings can be painted or coated further for additional protection. Limitations include wear or abrasion that exposes the base metal, reduced effectiveness in highly acidic or very aggressive environments, and the need for reapplication or re-galvanizing when the coating becomes too damaged.

Zinc-coated steel is widely used in construction (beams, fasteners, and fencing), transportation components, plumbing and electrical enclosures, roofing, pipes, and agricultural equipment.

Standards governing zinc coatings on steel include ISO 1461 for hot-dip galvanized coatings and EN 10240 for electroplated zinc coatings. The expected service life depends on exposure conditions, corrosion rate, and maintenance, with coastal and industrial environments generally reducing longevity.