Why Do Cold-rolled Steel Sheets Need To Be Pickled And How To Prevent Rust?

Cold-rolled steel plate is a steel plate processed by cold rolling process, which has the characteristics of high surface flatness, excellent mechanical properties, and simple processing technology. During the manufacturing process, the surface of cold-rolled steel sheets usually has iron oxide scale, oil stains and other impurities, which will affect the surface quality and performance of the material, so pickling treatment is required.
Pickling is to put the cold-rolled steel plate into the acid solution for corrosion treatment to remove the oxide scale, oil stain and other impurities on the surface. During the pickling process, the iron on the surface of the steel plate is corroded to form a layer of ferrite, which makes the surface more flat, clean and smooth.
Anti-rust treatment is the surface treatment of cold-rolled steel sheets to prevent the surface of the steel sheets from rusting. Commonly used methods include painting, spray painting, galvanizing, electrophoretic coating, etc., among which painting and spray painting are the most commonly used. Painting and spraying can form a protective layer to prevent the surface of the steel plate from contacting oxygen and moisture, so as to achieve the purpose of rust prevention. In addition, during transportation and storage, appropriate measures need to be taken, such as using moisture-proof packaging materials, adding ventilation equipment in the storage area, etc., to ensure the surface quality and performance of cold-rolled steel sheets.