Galvanized steel sheet is a welded steel sheet with a zinc layer formed on its surface through hot-dip galvanizing or electroplating processes. It is classified into electro-galvanized steel sheet (SECC), hot-dip galvanized steel sheet (SGCC), and aluminized zinc steel sheet (SGLD). This material is mainly used in construction, home appliances, vehicle and ship manufacturing, and electromechanical equipment. The zinc coating improves the corrosion resistance of the steel, and its thickness and zinc flower morphology directly affect its performance. Products must meet quality inspection standards such as zinc coating amount (measured in g/m²), flatness, and camber control.
The industrial production of galvanized steel sheet began in the United States in 1937 with the first hot-dip galvanizing production line. my country began building large-scale production lines in the late 1970s. Domestic companies such as Baosteel and Wuhan Iron and Steel are the main producers, but high-end products still rely on imports. In 2023, the sales volume of galvanized sheet (strip) showed a year-on-year decline, and prices exhibited cyclical fluctuations. In terms of exports, from January to October 2024, the export volume of coated steel sheets (strips) reached 15.8738 million tons, a year-on-year increase of 19.65%. The home appliance sector is the main application scenario for galvanized steel sheets, with air conditioner manufacturing playing a dominant role. In July 2024, the demand for galvanized steel sheets in the air conditioning industry reached 411,900 tons.
Galvanized steel sheets are divided into ordinary electrolytic sheets and fingerprint-resistant electrolytic sheets. Fingerprint-resistant sheets are ordinary electrolytic sheets with an added fingerprint-resistant treatment, making them resistant to sweat. They are generally used on parts that do not undergo any treatment and are designated SECC-N. Ordinary electrolytic sheets are further divided into phosphated sheets and passivated sheets. Phosphating is more commonly used, with the designation SECC-P, commonly known as P-material. Passivated sheets are available with or without oil coating.
