Hot-Dip Galvanized Steel Sheet is a steel product manufactured by immersing steel sheets—after cleaning and annealing—into molten zinc baths for coating treatment. This process forms a uniform, dense zinc-iron alloy coating on the steel surface.
1.Common Grades and Standards
| Standard System | Common Grades | Description |
| 中国 GB | DX51D+Z / DX52D+Z / DX53D+Z | Hot-dip galvanized steel for stamping and deep drawing: Higher numbers indicate better formability. |
| S250GD+Z / S350GD+Z | Hot-dip galvanized steel for structural use: Numbers denote strength. | |
| 欧洲 EN | DX51D / DX52D / S350GD | Similar to national standards, widely used in construction and manufacturing. |
| 美国 ASTM | A653 CS / A653 FS / A653 SS | CS (Commercial Grade), FS (Forming Grade), SS (Structural Grade). |
2.Differences from Ordinary Cold-Rolled Steel Sheets/Electrogalvanized Steel Sheets
| Comparison Item | Hot-Dip Galvanized Plate (HDG) | Electro-Galvanized Plate (EG) | Common Cold-Rolled Plate (CR) |
| Coating Thickness | Thick (usually 7-50m) | Thin (usually 3-10m) | No coating |
| Corrosion Resistance | Excellent, suitable for outdoor use | Good, suitable for indoor use | Poor, prone to rust |
| Cost | Medium | High | Low |
| Main Uses | Construction, roofing, outdoor structures | Home appliance panels, automotive inner panels | Stamping parts, substrates for painted parts |
