Fe-Zn GALVANNEALED STEEL SHEET (GA)

• Galvannealed steel sheet offers significant improvements in weldability and paintability by undergoing a simple pre-treatment process. After the coating process a special heat treatment forms an alloy layer between the galvanized layer and the metal base.
• Superior weldability : The weldability of galvanized sheet is drastically compromised because of the absorption of zinc coating onto the welding electrode. Galvannealed plates have significantly improved weldability because of the high melting point of FeZn alloy on the surface, which prevents electrode contamination.
• Greater peeling resistance : Due to exceptional paint adhesiveness resulting from the formation of alloy layers, the peeling resistance during the bending and folding treatment is greatly enhanced, compared to regular hot-dipped sheet.
• Superior paint adhesiveness and corrosion resistance : The rough alloy layers of the galvannealed sheet surface facilitates the reaction to the pre-treatment(Phosphate and chromate treatment), improving paint adhesiveness and corrosion resistance.
• Improvements in powdering : The FeZn alloy layer generally displays a high level of hardness and low ductility, causing the alloy layer on the surface to peel off as powder during deep drawing. Dongbu Steel's #3CGL uses the high frequency induction heat method during the heat treatment  that follows the coating phase, which drastically lowers the degree of powdering, presenting an elegant steel surface.