Galvanized Steel Sheet: Advanced Applications & Technical Specifications
Direct Coating Advantage
Hot-dip galvanized surfaces enable pretreatment-free adhesion of bituminous coatings (e.g., asphalt, coal-tar epoxy) due to:
- Optimal surface roughness: Ra 3-8 μm (ISO 4288)
- Zinc-iron alloy layer porosity: <5% (ASTM B117 salt spray compliance)
Industrial Application Matrix
1. Construction & Structural Engineering
- Roofing/Wall Systems:
- Material: Z275-Z450 HDG sheets (EN 10346)
- Thickness: 0.4-1.5mm with AZ150 coating
- Performance: 40-year lifespan in C4 marine environments
- Acoustic Barriers:
- 80-150mm composite panels with 2.0mm HDG substrate
- Sound reduction: 25-35 dB (ISO 717-1)
2. Automotive Engineering
- Exhaust Systems:
- Grade: HX340LAD+Z (EN 10346)
- Aluminized coating hybrid for 900°C thermal resistance
- Fuel Tanks:
- 1.2-2.0mm EG sheets (SECC, JIS G3302)
- Coating weight: 20/20 g/m² (double-sided)
3. Appliance Manufacturing
| Component | Material Specification | Key Requirement |
|---|---|---|
| Refrigerator Shell | SECC-SD, 0.6mm (JIS G3313) | ERC ≥12mm (deep drawing) |
| Microwave Cavity | HDG ZM310, 1.0mm (ASTM A653) | Non-sparking surface |
| Electrical Cabinets | Galvannealed (GA) 60/60 g/m² | Painted adhesion ≥4B |
4. Agricultural Infrastructure
- Livestock Housing:
- 0.7mm HDG sheets with micro-rib texture (anti-slip Rz=15-25μm)
- Coating: Z600 (600g/m²) for ammonia corrosion resistance
- Grain Storage:
- 2.0-3.0mm structural sections with 85μm Zn-Mg coating
5. Specialized Industrial Equipment
- Heat Exchangers:
- 0.3-0.8mm EG strips (CQ/FS/ED grades)
- Continuous service: -50°C~200°C
- Drying Chambers:
- HDG Z275 with silicone-modified polyester coating
Technical Comparison: HDG vs. EG
| Parameter | Hot-Dip Galvanizing (HDG) | Electrogalvanizing (EG) |
|---|---|---|
| Coating Thickness | 50-150 μm | 5-30 μm |
| Process Speed | 3-8 m/min | 10-30 m/min |
| Edge Protection | Full metallurgical bonding | Limited edge coverage |
| Cost Efficiency | $40-80/ton premium | $15-30/ton premium |
Certification & Compliance
- Construction: EN 10346, ASTM A653 (G90/G120)
- Automotive: ISO 3575, VDA 239-100
- Food Contact: FDA 21 CFR 175.300 compliant grades
Available in coil (0.3-3.0mm) or pre-cut blanks (≤12,000mm length). Custom Zn-Al-Mg coatings (5%Al-3%Mg) available for 3x enhanced corrosion resistance.
Product Parameters
| Product Name | Galvalume Steel Sheet |
| Thickness | 0.12mm-6.00mm |
| Width | 600mm-1500mm |
| Length | 1m-12m, Support Customization |
| Standard | AISI, ASTM, DIN, JIS, GB, JIS, SUS, EN, etc. |
| Thickness of Aluminum Zinc Coating | 30-185g/m² |
| Content of Al-Zn Coating | Al: 55%, Zn: 43.5%, Si: 1.5% |
Chemical Composition
| Al | Zn | Si | Fe | Cu | Cd | Pb | Sn | Ni | Close Cr |
| 55-58 | 41-43 | 1.5-2 | 0.25 | 0.03 | 0.05 | 0.01 | 0.05 | 0.05 | 0.05 |
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 | – |
Galvanized Surface Selection
| Type of Coating | Recommended Coating Weight |
| Aluminum-zinc Alloy | 30/40/50/60/75/90/100/150 |
| A: Coating quality50g/㎡,approximately equal to the coating thickness13.3pm | |
| Project | Classification | Symbol |
| Type of Coating | Aluminum-zinc Alloy | AZ |
| Surface Finish | Conventional Sequins | R |
| Minimize Sequins | M | |
| Skin Through | S | |
| Surface Treatment | Chromate Passivation | c |
| Non-chromate Passivation | C5 | |
| Chromate Passivationoiling | CO | |
| Chromium-free Passivationoiling | CO5 | |
| Anti-fingerprint | N | |
| Chromate-free/Anti-fingerprint | N5 | |
| No chromate high weather resistance fingerprint | NW | |
| Oil filling | 0 | |
| No treatment | U |
Material Comparison
|
Chinese Standard |
European Standards | American Standard | Japanese Standard |
| DC51D+AZ | DX51D+AZ | CS Type B, Type C | SGLCC |
| DC52D+AZ | DX52D+AZ | DS | SGLCD |
| S250GD+AZ | S250GD+AZ | 255 | – |
| S300GD+AZ | – | – | – |
| S350GD+AZ | S350GD+AZ | 345 | Class1 SGLC490 |
| S550GD+AZ | S550GD+AZ | 550 | SGLC570 |
Packing And Delivery
