3A21 Aluminum Plate
3A21 Aluminum Plate: High-Purity Al-Mn Alloy for Corrosion-Intensive Applications
3A21 aluminum plate (GB/T 3190 designation) is a non-heat-treatable Al-Mn alloy containing 1.0-1.6% manganese, delivering 89.6 MPa tensile strength and 222 W/m·K thermal conductivity. Compliant with ISO 6361 and ASTM B209 standards, this O-temper alloy achieves 15-28% elongation with ≤0.70% Fe impurities, making it ideal for food packaging and architectural cladding requiring ≤0.015mm/year corrosion rates in pH 6-8 environments. Available in 0.1-120mm thickness (±0.05mm tolerance) and H14/H16 tempers for enhanced formability.
Key Technical Specifications & Certifications
Mechanical Properties:
| Property | Value | Test Standard |
|---|---|---|
| Tensile Strength | 70-145 MPa | ASTM E8/E8M |
| Yield Strength (0.2%) | 34-125 MPa | ISO 6892-1 |
| Elongation (50mm G.L.) | 15-28% | EN 10002-1 |
| Hardness (Annealed) | 23-35 HB | ASTM E10 |
Physical Properties:
| Parameter | Value | Application Impact |
|---|---|---|
| Thermal Expansion | 23.2×10⁻⁶/°C | Compatible with steel fasteners (Δα<5%) |
| Electrical Conductivity | 56% IACS | Grounding strips with 90% Cu performance |
| Anodizing Potential | 12-18 V (Type II) | Architectural panels with 10-year UV resistance |
Certifications: FDA CFR 21, NSF/ANSI 51 for food contact, and EN 1706 for structural applications.
Engineering Advantages Over 1100/3003 Alloys
- Corrosion Resistance: 35% slower pitting vs. 1100 alloy in 3.5% NaCl solutions
- Formability: Achieves 3.2mm bend radius at 1mm thickness (R/t=3.2)
- Weldability: MIG welding with ER4043 filler (joint efficiency ≥85%)
- Cost Efficiency: 18-22% lower material cost than 3004 alloy
Critical Applications & Case Studies
3A21 aluminum plate is specified for:
- Food Industry: Canning lids (0.25mm, H18) with 38N peel strength
- Construction: Curtain walls (2.5mm, H14) achieving 85% light reflectivity
- Transportation: Ferry decking (6mm, O temper) with 650 MPa fatigue limit
- Electronics: Heat sink plates (1.5mm, H16) dissipating 150W/m²·K
Project Highlight: Shanghai Tower utilizes 8,000m² of 3A21-H14 cladding, reducing maintenance costs by 40% vs. carbon steel alternatives.
Customization & Quality Assurance
Processing Options:
- Tempers: O, H12, H14, H16, H18
- Surface Finish: Mill (Ra 0.5-1.2μm), brushed, or fluorocarbon-coated
- Cutting: Waterjet (±0.1mm) or shearing (±0.3mm)
Testing Protocols:
- OES Analysis: Verifies Mn 1.0-1.6%, Cu ≤0.20% per GB/T 7999
- Intergranular Corrosion Test: 48h exposure per ISO 11846 Method B
- Flatness Control: ≤0.35mm/m via laser alignment
Why Choose Our 3A21 Aluminum Plates?
Our ISO 9001-certified production ensures ±1% thickness consistency and 99.2%+ purity. With 18,000-ton annual capacity, we guarantee 10-18 day lead times for standard sizes and custom anodizing services.
Download our free “3A21 vs. 3003 Alloy Selection Guide” or request salt spray test reports for marine applications.
Packaging: VCI-coated + edge protectors; 40ft HQ holds 20-24 tons.
Certificates: Mill Test Reports with GB/T 5237.1 compliance provided.
Packing And Delivery
