Pickling (metal)

"Pickled" redirects here. For the removal of layers of paints or varnishes, see paint stripping. Pickling is a surface treatment of metals used to remove impurities, such as stains, inorganic contaminants, rust or slag, ferrous metal alloys, copper, and aluminum.A solution is used called passivation liquor, which contains strong acids, to remove surface impurities. It is usually used to remove slag or clean steel in various manufacturing processes of mechanical components, before other operations such as extrusion, welding, painting, silver. Bibliography

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