G40 Galvanized Coil Product Overview
The G40 Galvanized Coil (ASTM A653 designation) features a total zinc coating weight of 40 oz/ft² (≈122 g/m²), delivering 8–12 years of corrosion resistance in moderate environments. Produced via continuous hot-dip galvanizing at 450–465°C, this cold-rolled carbon steel substrate achieves 220–550 MPa yield strength with ≥15% elongation, making it ideal for roofing, HVAC systems, and agricultural equipment. Compliant with ASTM A653 (G40) and EN 10346 (Z120), it bridges affordability and performance, offering 30% lower lifecycle costs than stainless steel.
Key Technical Specifications
1. Dimensional & Coating Properties
- Base Steel Thickness: 0.12–3.5 mm (±3% tolerance per ASTM A924)
- Width: 600–1,500 mm (custom slitting for roll-forming compatibility)
- Zinc Coating:
- Total Weight: 40 oz/ft² (122 g/m²) – 18–24 µm per side
- Adhesion Strength: ≥2.8 N/mm² (ISO 2409 cross-hatch test)
- Surface Finish:
- Zero Spangle (Z): Smooth, spangle-free (Ra ≤0.8 µm) for painting
- Minimized Spangle (M): Fine crystalline texture (Ra 1.2–2.5 µm)
2. Mechanical & Chemical Performance
| Grade | Yield (MPa) | Tensile (MPa) | Elongation (%) | Bendability |
|---|---|---|---|---|
| G40 (A653) | 220–380 | 270–500 | ≥22 | 0T–2T (0.8 mm) |
| S350GD+Z (EN) | ≥350 | ≥420 | ≥16 | 1T–3T (1.2 mm) |
| SGCD2 (JIS) | ≥220 | ≥300 | ≥22 | 0T–2T (1.0 mm) |
Chemical Composition:
| Element | G40 (ASTM) | S350GD (EN) | SGCD2 (JIS) |
|---|---|---|---|
| Carbon (C) | ≤0.15% | ≤0.20% | ≤0.10% |
| Manganese (Mn) | ≤0.60% | ≤0.70% | ≤0.45% |
| Phosphorus (P) | ≤0.10% | ≤0.10% | ≤0.03% |
Corrosion Resistance by Application
| Environment | Recommended Coating | Service Life | Key Industries |
|---|---|---|---|
| Indoor Dry Storage | Z10 (100 g/m²) | 8–10 years | Warehousing, Retail |
| Suburban Residential | G40 + Paint (2 layers) | 12–15 years | Roofing, Gutters |
| Industrial Zones | Z27 (270 g/m²) | 10–12 years | Machinery, Ductwork |
| Coastal (500m) | Z27 + Chromate Passivation | 8–10 years | Offshore Equipment |
Surface Treatment Options
| Code | Treatment | Benefits | Applications |
|---|---|---|---|
| C | Chromate-Free Passivation | RoHS-compliant, enhances salt spray resistance by 25% | Solar panel frames |
| P | Zinc Phosphate + Sealing | Paint adhesion >7 MPa (ISO 2409) | Pre-painted wall cladding |
| Q | Oiling + Phosphating | Prevents white rust during海运 transit | Export-ready structural parts |
| M | Mill Finish | Ready for post-fabrication painting | Custom industrial components |
Global Standard Equivalents
| USA (ASTM) | Europe (EN) | Japan (JIS) | China (GB) |
|---|---|---|---|
| G40 | Z120 | SGCC Z12 | DC51D+Z120 |
| SS275 | S275GD+Z | SGC340 | B280VK+Z |
Sustainability & Certifications
- Recycled Content: 25–35% (ISO 14021-certified)
- Carbon Footprint: 1.4 tons CO₂/ton (EPD verified)
- Certifications: RoHS, REACH, LEED v4.1, ISO 9001
Packing And Delivery
