Z120 Galvanized Coil Product Overview
The Z120 Galvanized Coil features a total zinc coating of 120 g/m² (dual-sided), equivalent to 36 g/m² per three-point test or 90 g/m² single-spot measurement, achieving 8–15 years of corrosion resistance in moderate environments. Produced via continuous hot-dip galvanizing (HDG) at 460–500°C, this cold-rolled carbon steel substrate meets ASTM A653 (G40) and EN 10346 (Z120) standards, delivering 220–380 MPa yield strength and ≥22% elongation for commercial roofing, HVAC ductwork, and appliance manufacturing.
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 (precision-slitted for roll-forming)
- Zinc Coating:
- Total Weight: 120 g/m² (≈17 µm total thickness)
- Adhesion Strength: ≥2.5 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)
2. Mechanical Performance
| Grade (EN 10346) | Yield Strength (MPa) | Tensile Strength (MPa) | Elongation (%) |
|---|---|---|---|
| DX51D+Z120 | 240–380 | 270–500 | ≥22 |
| S220GD+Z120 | ≥220 | ≥300 | ≥20 |
| S350GD+Z120 | ≥350 | ≥420 | ≥16 |
Functional Metrics:
- Bendability: 0T–2T (180° bend @ 0.8 mm thickness)
- Salt Spray Resistance: 1,200–1,800 hours (ISO 9227)
- Weldability: 8–12 kA spot welding current (AWS C1.1 compliant)
Chemical Composition
| Grade | C (%) | Si (%) | Mn (%) | P (%) | S (%) |
|---|---|---|---|---|---|
| DX51D+Z120 | ≤0.12 | ≤0.50 | ≤0.60 | ≤0.10 | ≤0.045 |
| SGCD1+Z120 (JIS) | ≤0.12 | ≤0.50 | ≤0.60 | ≤0.04 | ≤0.03 |
| S350GD+Z120 | ≤0.20 | ≤0.60 | ≤0.70 | ≤0.10 | ≤0.045 |
Key Features:
- Ultra-Low Carbon: Reduces weld brittleness risk.
- Manganese Optimization: Balances formability and tensile strength.
Environmental Performance
| Exposure | Coating | Service Life |
|---|---|---|
| Indoor (Dry) | Z120 (Unpainted) | 12–15 years |
| Suburban | Z120 + Paint (2 layers) | 15–20 years |
| Industrial | Z120 + Chromate Passivation | 10–12 years |
| Coastal (500m) | Z120 + Z275 Overcoat | 8–10 years |
Surface Treatment Options
| Code | Treatment | Benefits |
|---|---|---|
| C | Chromate-Free Passivation | RoHS-compliant, 30% higher salt spray resistance |
| P | Zinc Phosphate + Sealing | Paint adhesion >7 MPa (ISO 2409) |
| O | Anti-Fingerprint Oiling | Prevents white rust during海运 storage |
| M | Mill Finish | Immediate post-production painting |
Applications
- Architecture: Roofing panels, rainwater systems.
- Automotive: Exhaust shields, structural reinforcements.
- Agriculture: Grain storage bins, equipment housings.
- Energy: Solar panel frames, transformer casings.
Global Standard Equivalents
| USA (ASTM) | Europe (EN) | Japan (JIS) | China (GB) |
|---|---|---|---|
| G40 | Z120 | SGCC Z12 | DC51D+Z120 |
| SS275 | S275GD+Z | SGHC275 | B280VK+Z |
Sustainability & Compliance
- Recycled Content: 25–35% (ISO 14021 certified).
- Carbon Footprint: 1.3 tons CO₂/ton (EPD verified).
- Certifications: RoHS, REACH, LEED v4.1, ISO 9001.
Packing And Delivery
