structural galvanized steel
S280GD and S320GD are structural galvanized steel grades specified under EN 10346, widely used in construction, steel structures, and industrial systems that require both mechanical strength and corrosion resistance.
The designation system is straightforward: "S" refers to structural steel, the numbers 280 and 320 indicate the minimum yield strength in MPa, and "GD" means the steel is delivered in galvanized condition, typically through hot-dip galvanizing.
Both S280GD Galvanized Steel and S320GD Galvanized Steel are designed to meet modern structural requirements, but their mechanical performance and application focus differ in practical use.
Mechanical Property Comparison
The difference in yield strength between S280GD and S320GD directly affects load-bearing capacity, section design, and material efficiency.
| Mechanical Property | S280GD | S320GD |
|---|---|---|
| Minimum Yield Strength | ≥ 280 MPa | ≥ 320 MPa |
| Tensile Strength | 360–480 MPa | 390–510 MPa |
| Elongation (A80) | ≥ 18% | ≥ 17% |
| Strength Category | Medium | Medium–High |
S320GD provides higher strength, allowing engineers to reduce thickness while maintaining structural safety, whereas S280GD offers slightly better forming tolerance.
In real fabrication environments, forming behavior often plays a decisive role in grade selection.
| Processing Aspect | S280GD Galvanized Steel | S320GD Galvanized Steel |
|---|---|---|
| Cold forming | Very good | Good |
| Bending radius tolerance | Wider | Moderate |
| Roll forming stability | High | Medium–High |
| Risk during complex profiling | Lower | Slightly higher |
For projects involving complex profiles or frequent bending operations, S280GD Galvanized Steel is often preferred. S320GD, however, remains suitable for standard structural forming processes.
Application Differences
- S280GD Galvanized Steel is widely used in:
Light steel structures
Roofing and wall cladding systems
Purlins and secondary framing
- S320GD Galvanized Steel is more commonly selected for:
Medium-load structural members
Industrial frames
Applications requiring higher stiffness
The choice depends on whether forming flexibility or strength optimization is the primary concern.
Available Steel Grade
|
Standard |
Grade |
C |
Si |
Mn |
P |
S |
Ti |
|
Forcold Forming Chinese Standard |
DX51D+Z |
0.12 |
0.50 |
0.60 |
0.100 |
0.045 |
0.30 |
|
DX52D+Z |
0.12 |
0.50 |
0.60 |
0.100 |
0.045 |
0.30 |
|
|
DX53D+Z |
0.12 |
0.50 |
0.60 |
0.100 |
0.045 |
0.30 |
|
|
DX54D+Z |
0.12 |
0.50 |
0.60 |
0.100 |
0.045 |
0.30 |
|
|
DX56D+Z |
0.12 |
0.50 |
0.60 |
0.100 |
0.045 |
0.30 |
|
|
DX57D+Z |
0.12 |
0.50 |
0.60 |
0.100 |
0.045 |
0.30 |
|
|
Forcold Forming Japanese Standard |
SGCC |
0.15 |
0.50 |
0.80 |
0.050 |
0.030 |
0.025 |
|
SGCD1 |
0.12 |
0.50 |
0.60 |
0.040 |
0.030 |
0.025 |
|
|
SGCD3 |
0.08 |
0.50 |
0.45 |
0.030 |
0.030 |
0.025 |
|
|
SGCD4 |
0.06 |
0.50 |
0.45 |
0.030 |
0.030 |
0.025 |
|
|
For Structure Japanese Standard |
SGC340 |
0.25 |
0.50 |
1.70 |
0.200 |
0.035 |
0.025 |
|
SGC400 |
0.25 |
0.50 |
1.70 |
0.200 |
0.035 |
0.150 |
|
|
SGC490 |
0.30 |
0.50 |
2.00 |
0.200 |
0.035 |
0.025 |
|
|
SGC510 |
0.30 |
0.50 |
2.50 |
0.200 |
0.035 |
0.025 |
|
|
For Structure AISI Standard |
S220GD+Z |
0.20 |
0.60 |
0.70 |
0.100 |
0.045 |
0.025 |
|
S250GD+Z |
0.20 |
0.60 |
0.70 |
0.100 |
0.045 |
0.025 |
|
|
S280GD+Z |
0.20 |
0.60 |
0.70 |
0.100 |
0.045 |
0.025 |
|
|
S320GD+Z |
0.20 |
0.60 |
0.70 |
0.100 |
0.045 |
0.025 |
|
|
S350GD+Z |
0.20 |
0.60 |
0.70 |
0.100 |
0.045 |
0.150 |
|
|
S550GD+Z |
0.20 |
0.60 |
0.70 |
0.100 |
0.045 |
0.150 |
- Mechanical Properties
|
Grade |
Yield Strength MPa≥ |
Tensile Strength MPa≥ |
Elongation A%≥ |
|
DX51D Z/ZM/AZ/AM |
240-380 |
270-500 |
22 |
|
DX52D Z/ZM/AZ/AM |
140-300 |
270-420 |
26 |
|
DX53D Z/ZM/AZ/AM |
140-260 |
270-380 |
30 |
|
DX54D Z/ZM/AZ/AM |
120-220 |
260-350 |
36 |
|
S220GD Z/ZM/AM |
220 |
300 |
20 |
|
S250GD Z/ZM/AZ/AM |
250 |
330 |
19 |
|
S280GD Z/ZM/AM |
280 |
360 |
18 |
|
S300GD A/AM |
300 |
380 |
18 |
|
S320GD Z/ZM/AM |
320 |
390 |
17 |
|
S350GD Z/ZM/AZ/AM |
350 |
420 |
16 |
|
S450GD A/AM |
450 |
480 |
15 |
|
S550GD Z/ZM/AZ/AM |
550 |
550 |
- |
GNEE STEEL supplies both S280GD and S320GD Galvanized Steel with consistent mechanical properties, uniform zinc coating, and strict quality control.
In addition to these grades, GNEE STEEL also offers S250GD, S350GD, DX51D, and DX54D galvanized steel products, supporting a wide range of structural and industrial applications.