Galvanic zinc plating
Service description
During galvanic plating, cations of one metal are transferred to the surface of another metal (electrolysis) using electrical energy. Everything takes place by electrochemical reaction in a liquid electrolyte environment. Zinc, nickel, chromium and others can be used as metals for plating. Parts can be hung on a hanger or immersed in a drum. The most commonly used metal is zinc, the color can be white (blue), olive, black or yellow. This technology is not suitable as anti-corrosion protection for outdoor environments. The standard coating thickness is 8–15 microns, maximum 35 microns.
Hot-dip galvanizing
Service description
It is carried out by immersing steel structures in a zinc bath with a temperature of approximately 450 to 470 degrees. Due to the mutual reaction of the base material and zinc, a solid layer is formed on the surface of the steel. If this layer does not react with iron during cooling, then the surface is metallically shiny. When alloying elements (tin, lead) are used, the surface layer crystallizes and creates a so-called zinc bloom. It is very important to monitor the content of silicon and phosphorus in steel. Their concentration significantly affects the thickness of the zinc layer. The standard thickness is 70 to 150 microns. Annual zinc loss is approximately 1.2 microns. Hot-dip galvanizing is suitable as an anti-corrosion protection for outdoor environments.
