What is the material of S350GD hot dip galvanized steel?
S350GD hot-dip galvanized steel coil:
S: Structural Steel
350: Minimum yield strength 350 MPa (higher than ordinary DX51D)
GD: Galvanized by Hot-Dip Process
+Z: Hot-dip galvanized layer (Zinc Coating), such as Z275 means the total weight of the double-sided zinc layer is 275g/m².
Mechanical properties:
Yield strength: ≥350 MPa
Tensile strength: 420-510 MPa
Elongation: ≥18% (suitable for cold bending)
Anti-corrosion performance:
The zinc layer provides 10-30 years of corrosion protection (depending on the environment), and aluminum zinc plating (AZ150) is optional for harsh environments
What is S350GD+Z steel equivalent to?
European standard EN 10346 S350GD corresponds to:
American standard A653 SS50 (strength 345MPa)
National standard GB/T 2518 S350GD (same parameters)
Japanese standard JIS SGHC (strength test required)
What are the types of S350GD steel zinc layers?
Pure zinc coating (Z):
Zinc liquid composition: 99.95% pure zinc + 0.03% aluminum
Coating structure: η phase (pure zinc layer) + ζ phase (FeZn13)
Aluminum zinc coating (AZ):
Zinc liquid composition: 55%Al+43.5%Zn+1.5%Si
Corrosion resistance is 2-4 times that of pure zinc
What is the difference between S350GD steel and stainless steel?
S350GD+Z is galvanized carbon steel. Unlike stainless steel (such as 304/316), its corrosion protection relies on sacrificial protection of the zinc layer rather than a chromium passivation film.
Application of S350GD+Z steel in construction
(1) Load-bearing structure
Industrial plant: roof trusses, purlins, support beams
Warehouse/logistics center: large shelves, steel structure frames
Bridges/passages: secondary load-bearing components (need to be combined with anti-corrosion design)
(2) Enclosure system
Metal roof/wall: combined with profiled sheets (such as corrugated sheets, trapezoidal sheets)
Ventilation ducts: better weather resistance than ordinary cold-rolled steel
(3) Special scenarios
Coastal/high humidity areas: S350GD+Z275 or S350GD+AZ150 is recommended
Chemical zone: PVDF coating can be added to improve chemical corrosion resistance