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Hot-dip galvanizing (HDG) is the process of giving a coat of galvanic coating to steel parts. by immersing in a bath of molten zinc at about 450 deg C. While it is mainly used for higher thickness materials such as angles, channels poles, etc., sheets from 3 mm upwards too can be galvanized. Below 3 mm the sheet will warp due to the heat. Zinc, aluminium, tin, lead, and lead alloyed with 10 to 20 percent in are commonly used for hot-dip coatings.