Elektrogalvaanointi

Elektrogalvaanointi, also known as electro galvanization, is a metal surface treatment that involves depositing a thin layer of zinc onto a ferrous substrate through electroplating. The process begins with cleaning and degreasing the metal part, followed by an acid pickling step to remove any surface oxides. After rinsing, the workpiece is immersed in a zinc sulfate electrolyte solution. An electric current is applied, with the part serving as the cathode and a zinc anode floating in the bath. Zinc ions in the electrolyte migrate to the cathode and reduce, forming a continuous zinc coating. Upon completion, the component is rinsed, dried, and may undergo a thermally activated hardening step to improve coating adhesion and uniformity.

Electrogalvanization offers several advantages. The coating thickness can be precisely controlled, typically ranging from a few micrometers up to a few hundred micrometers, which is advantageous for parts where weight or dimensional tolerance is critical. The process operates at relatively low temperatures, making it suitable for plated-on decorative surfaces and for substrates that are sensitive to high heat. The zinc layer provides sacrificial protection against corrosion; when the coating is damaged, the underlying metal remains protected until the zinc corrodes. In addition, electrogalvanized zinc is bright, white and can be finished with clear or colored top coats.

Compared to hot‑dip galvanization, electrogalvanization generally yields a thinner coating, lower zinc usage, and avoids the high temperatures used in fluxing baths. However, it offers less mechanical robustness against abrasion and impact; the coating can be more susceptible to mechanical wear. Typical applications include automotive trim, household appliances, kitchenware, and structural steel components where moderate corrosion resistance is required. The method also aligns well with modern environmental regulations, as most electroplating baths can be treated to remove toxic waste.