Common Types of Galvanized Steel Sheet and Their Applications

Galvanized steel sheets (GI sheets) are classified based on coating methods, surface finishes, and material grades.

Types of Galvanized Steel Sheets

Galvanized steel sheets (GI sheets) are classified based on coating methods, surface finishes, and material grades. Here's a quick overview:

1. By Coating Method

• Hot-Dip Galvanized (HDG):
  Dipped in molten zinc. Strong corrosion resistance. Common grade: DX51D+Z.

• Electro-Galvanized (EG):
  Electroplated zinc layer. Smooth surface, ideal for painting and indoor use.

2. By Surface Finish

• Regular Spangle:
  Visible crystal pattern, common in general construction.

• Zero Spangle:
  Smooth finish, good for painting and decorative use.

3. By Steel Grade

• DX51D: Standard commercial quality.

• DX52D / DX53D: Higher formability for deep drawing.

• SGCC: JIS standard, similar to DX51D.

Conclusion:
Choosing the right galvanized sheet type ensures better performance in different environments—from roofing to appliances.