S320GD Steel Grades
High-Strength Hot-Dip Galvanized Structural Steel for Construction and Industrial Applications
- Technical Support
S320GD Steel Technical Specifications & Applications
S320GD is a high-strength hot-dip galvanized structural steel grade compliant with EN 10346, offering a minimum yield strength of 320 MPa. It combines strength, formability, and corrosion resistance, making it suitable for various applications in construction and manufacturing.
This steel grade is widely used in structural framing, purlins, and heavy-duty roll-formed sections. Its excellent weldability and cold-forming properties allow for efficient processing in bending, cutting, stamping, and roll-forming operations.
Manufactured under stringent quality controls, S320GD meets international standards, ensuring reliable performance in galvanized and structural steel applications.
As a core product of Hengze Steel Group, S320GD is trusted globally for durable, high-performance galvanized structural steel solutions in construction, engineering, and manufacturing sectors.
Table of Contents
1. Typical Uses & Selection Guidance
- Structural Applications
S320GD is a high-strength hot-dip galvanized structural steel grade compliant with EN 10346, featuring a minimum yield strength of 320 MPa. It offers an optimal balance of strength, formability, and corrosion resistance, making it suitable for various applications in construction and manufacturing.
- Corrosion Protection
When hot-dip galvanized or metallic-coated (Zinc, Zinc-Aluminium), S320GD provides reliable corrosion resistance for roofing, wall cladding, gutters, and general building applications, particularly in mild to moderate environments. The zinc coating offers a robust barrier against corrosion, extending the life of the steel.
- Forming Advantages
The higher yield strength of S320GD allows for easier bending, tighter radii, and reduced risk of cracking, making it ideal for complex profiles, detailed fabrication, and applications requiring superior formability.
2. Technical Specifications Table
1. Chemical Composition Requirements (Maximum %)
| Steel Grade | Carbon (C) | Manganese (Mn) | Phosphorus (P) | Sulfur (S) | Silicon (Si) | Aluminum (Al) |
|---|---|---|---|---|---|---|
| S280GD | ≤ 0.20% | ≤ 1.70% | ≤ 0.10% | ≤ 0.045% | ≤ 0.60% | — |
2. Mechanical Property Requirements (Maximum Values)
| Steel Grade | Min. Yield Strength (MPa) | Min. Tensile Strength (MPa) | Min. Elongation (%) Lo=80mm | Bend Angle (°) | Mandrel Diameter (× Thickness t) |
|---|---|---|---|---|---|
| S320GD | ≥ 320 | 390–530 | ≥ 17 | 90 | 6t |
3. Coating Adhesion (180° Bend Test) Requirements
| Coating Class | Mandrel Diameter (× Thickness t) |
|---|---|
| Z100, Z200 | 1t |
| Z275, Z350, Z450, AZ150, AZ200, AM100, AM125, AM150, AM175, AM200, AM225 | 2t |
| Z600 | 3t |
4. Applicable Hot-Dip Metallic Coating Types
| Coating Class | Composition (%) | Key Features |
|---|---|---|
| Z (Zinc) | ≥99% Zinc | Basic corrosion protection; suitable for general use. |
| ZA (Zinc-Aluminium) | 95% Zn, 5% Al | Improved corrosion resistance over pure zinc. |
| ZF (Zinc-Iron) | Zinc with iron alloy | Enhanced hardness and wear resistance. |
| ZM (Zinc-Magnesium) | Zn with 2–4% Mg, 5–13% Al | Superior corrosion resistance in harsh environments. |
| AZ (Aluminium-Zinc) | 55% Al, 43.5% Zn, 1.5% Si | Excellent corrosion resistance and heat reflectivity. |
| AM (Aluminium-Magnesium) | Al with Mg alloy | High corrosion resistance; suitable for high-temperature applications. |
3. S320GD vs S350GD — What’s the Difference?
| Property | S320GD Steel | S350GD Steel |
|---|---|---|
| Yield Strength | ≥ 320 MPa | ≥ 350 MPa |
| Tensile Strength | 390–510 MPa | 420–550 MPa |
| Elongation (80mm) | ≥ 17% | ≥ 16% |
| Bendability | 180° with 6t mandrel | 180° with 6t mandrel |
S320GD Steel FAQ：
S320GD is a high-strength, hot-dip galvanized structural steel grade compliant with EN 10346. It offers a minimum yield strength of 320 MPa and a tensile strength ranging from 390 to 510 MPa. This steel combines excellent formability with enhanced corrosion resistance, making it suitable for various applications in construction, automotive, and appliance manufacturing.
S320GD steel is widely used in constructing roofs, enclosures, and other structural components due to its good weldability, strength, and corrosion resistance. Its high-quality finish makes it suitable for both visible and structural applications.
S320GD can be supplied with a variety of hot-dip metallic coatings to enhance corrosion resistance:
Z (Zinc) – basic corrosion protection for general environments.
ZA (Zinc-Aluminium) – improved corrosion resistance over pure zinc.
ZF (Zinc-Iron) – increased hardness and wear resistance.
ZM (Zinc-Magnesium) – superior corrosion protection in harsh conditions.
AZ (Aluminium-Zinc) – excellent corrosion and heat reflectivity.
AM (Aluminium-Magnesium) – high corrosion resistance, suitable for high-temperature applications.
These coatings ensure long-lasting performance under diverse environmental conditions.
S320GD steel coils are manufactured in a range of thicknesses, typically from 0.35 mm to 0.50 mm, with widths and lengths tailored to project requirements. All coils comply with EN 10346 standards for galvanized structural steel, ensuring consistent quality, mechanical performance, and corrosion protection.
