Q：What is the difference between the production processes of electrogalvanizing and cold-rolled galvanizing?
A：Electrogalvanizing: Also known as cold galvanizing, it uses the principle of electrolysis to use zinc ingots as anodes. Zinc atoms lose electrons and become ions that dissolve into the electrolyte, while steel strips serve as cathodes. Zinc ions gain electrons on the steel strips and are reduced to zinc atoms that are deposited on the surface of the steel strips to form a coating.
Cold-rolled galvanizing: On the basis of cold-rolled steel strips, a layer of zinc is plated on the surface of the steel strips through electroplating or hot-dip processes. Cold-rolled steel strips are rolled by rolling mills at room temperature, with thinner thickness and smoother surface.
Q：What are the differences in coating properties?
A：Electrogalvanizing: The zinc layer is usually thinner, generally 3-15 microns. The coating is uniform, dense, well bonded, and has a smooth surface, but it may be gray and dirty. However, its processing performance is good. Since the zinc layer is relatively pure, it is not easily corroded in acid or alkaline environments, and can effectively protect the steel body for a long time.
Cold-rolled galvanizing: If the electroplating process is used, the coating characteristics are similar to those of electrogalvanizing; if the hot-dip process is used, the zinc layer is relatively thick and has a stronger anti-corrosion ability. The surface quality of cold-rolled galvanized products is better, without defects such as oxidation, spots, and flow marks, because the cold rolling process makes the surface of the steel strip smoother, and the cooling speed of the galvanized layer is slower, which is not easy to produce oxidation.
Q：What are the differences in application scenarios between electrogalvanizing and cold-rolled galvanizing?
A：Electrogalvanizing: It is often used for small parts that have certain requirements for corrosion resistance and high processing accuracy and surface quality, such as electronic equipment housings, automotive parts, hardware products, etc. It is also widely used in products that require subsequent painting or other surface treatments, because the electrogalvanized layer can provide a good base and help improve the adhesion of the coating.
Cold-rolled galvanizing: It is suitable for occasions requiring high surface quality and processing performance in industries such as home appliances, automobiles, construction, and ships. For example, the housings of home appliances, the body panels of automobiles, and the decorative panels in buildings may all use cold-rolled galvanized sheets.
Q：What are the differences in production costs?
A：Electrogalvanizing: The process is relatively complicated, requiring a large amount of electricity and chemicals, and the production efficiency is relatively low, so the cost is high and the price is expensive.
Cold-rolled galvanizing: If it is cold-rolled electroplating, the cost is not low; but if it is cold-rolled hot-dip, the hot-dip process has a high production efficiency and is suitable for large-scale production. In the case of large output, the unit cost is relatively low.
Q：Which industries are more suitable for using cold-rolled galvanized products?
A：Construction industry, automobile industry, home appliance industry, packaging industry, shipbuilding industry, electronic equipment industry, hardware industry, power industry.