Z275 Galvanized Coil Product Overview
The Z275 Galvanized Coil features a 275 g/m² zinc coating (≈80 µm thickness) applied through continuous hot-dip galvanizing, delivering 25–50 years of corrosion resistance in harsh coastal and industrial environments. Compliant with ASTM A653 (G90) and EN 10346 (Z275) standards, this cold-rolled carbon steel substrate achieves 350–550 MPa yield strength while maintaining ≥15% elongation, making it ideal for structural applications like solar farm mounts, highway guardrails, and offshore platforms.
Technical Specifications
1. Dimensional & Coating Properties
- Base Steel Thickness: 0.12–3.5 mm (±3% tolerance per ASTM A924)
- Width: 600–1,500 mm (precision-slitted for roll-forming machinery)
- Zinc Coating:
- Z275 (G90): 275 g/m² (80 µm) per side – 3.5x thicker than standard Z60 coatings
- Adhesion Strength: ≥3 N/mm² (ISO 2409 cross-cut 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)
- Large Spangle: Aesthetic finish for non-critical outdoor use
2. Mechanical & Chemical Performance
| Property | Z275 (G90) | DX51D+Z | S550GD+Z |
|---|---|---|---|
| Yield Strength (MPa) | 220–550 | 240–380 | ≥550 |
| Tensile Strength (MPa) | 300–550 | 270–500 | ≥550 |
| Elongation (%) | ≥15 | ≥22 | – |
| Bendability | 0T–3T | 0T–2T | 1T–4T |
Key Features:
- Ultra-Low Carbon (≤0.15%): Enhances weldability with 10–15 kA spot welding current.
- Zinc-Iron Alloy Layer: 1–3 µm Fe-Zn intermetallic bond for peel resistance during stamping.
Corrosion Resistance by Environment
| Environment | Coating | Service Life |
|---|---|---|
| Indoor (Low Humidity) | Z100 (100 g/m²) | 15–20 years |
| Suburban | Z200 + Paint | 20–30 years |
| Industrial | Z275 (Unpainted) | 25–35 years |
| Coastal (500m from sea) | Z275 + Chromate Passivation | 40–50 years |
Surface Treatment Options
| Code | Treatment | Benefits | Applications |
|---|---|---|---|
| C | Chromate-Free Passivation | RoHS-compliant, salt spray resistance +30% | Offshore wind turbine components |
| P | Zinc Phosphate + Sealing | Paint adhesion >8 MPa (ISO 2409) | Pre-painted roofing systems |
| Q | Oiling + Phosphating | Prevents white rust during海运 | Export-grade structural beams |
| M | Untreated (Mill Finish) | Immediate post-fabrication painting | Custom architectural cladding |
Global Standard Equivalents
| USA (ASTM) | Europe (EN) | Japan (JIS) | China (GB) |
|---|---|---|---|
| G90 | Z275 | SGCC Z27 | DC51D+Z275 |
| SS550 | S550GD+Z | SGC550 | S550GD+Z |
Sustainability & Compliance
- Recycled Content: 30–40% (certified per ISO 14021)
- Carbon Footprint: 1.2 tons CO₂/ton (verified by EPD International)
- Certifications: RoHS, REACH, Cradle-to-Cradle Bronze, LEED v4.1
Packing And Delivery
