China Hot-Dip Galvanized Coil Suppliers - Galvannealed Coils from Reliable Factory with Superior Weldability

Galvannealed (GA) coils, manufactured through an advanced two-step process, feature a hot-dip zinc coating followed by in-line annealing at temperatures between 500–550°C. This meticulous thermal treatment diffuses iron into the zinc layer, resulting in a Zn-Fe intermetallic alloy with 7–15% Fe content, enhancing weldability and abrasion resistance. With a matte-gray finish that meets ASTM A653 Grade GA60-GA165 standards, these coils provide a phosphate-free surface, perfect for optimal paint adhesion. Our cutting-edge air-knife system ensures precise control of coating weight within ±5 g/m² accuracy, achieving a total coating weight of 60–180 g/m² on both sides, complemented by a microhardness rating of 250–350 HV. As a leading manufacturer and supplier of Galvannealed coils in China, our factory is dedicated to delivering high-quality products tailored to meet your specific industrial needs