Process

Steel is cleaned by pickling it in diluted hydrochloric acid. Pickling removes rust and mill scale. The objects are then rinsed with water and dipped into a flux bath, giving them a protective layer of salt to prevent oxidation of the steel before the actual zinc bath. After the cleaning phases, the objects are immersed in molten (450°C) zinc. Zinc and pure steel react with each other and form a coating (3-layer phase bond + pure zinc). The thickness of the coating varies between 40 to 200 microns, depending on the silicon content of the steel, the thickness of the material being coated, and the immersion time.

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