In the three most demanding industrial applications — shipbuilding, LNG storage tanks, and military armor — 5083 aluminum plate is the only aluminum alloy that simultaneously meets the requirements of seawater corrosion resistance, excellent weldability, and sufficient structural strength.
ASTM B928 is specifically established for marine-grade aluminum plates, and 5083-H116 is its mandatory designated material. Mainstream global classification societies, including DNV·GL, ABS, LR, CCS, BV, NK, and KR, all recommend it as the standard material for hull plates.
What is 5083 Aluminum Alloy?
As a non-heat-treatable, high-magnesium anti-rust aluminum alloy, 5083 combines top-tier strength in its category with excellent weldability and good formability. With its ultimate seawater corrosion resistance derived from an exclusive "high-magnesium, low-copper" formula, it is the preferred material for severe environments such as shipbuilding, rail transit, and pressure vessels.
Standards and Aliases
| Standard System | Grade / Designation |
|---|---|
| USA (UNS) | A95083 |
| Europe (EN) | EN AW-5083 / AlMg4.5Mn0.7 |
| Executive Standards | ASTM B209 / ASTM B928 / EN 485 / GB/T 3880 |
Chemical Composition (ASTM B209 / B928)
| Element | Mg | Mn | Cr | Fe | Si | Cu | Zn | Ti | Al |
|---|---|---|---|---|---|---|---|---|---|
| Content (%) | 4.0–4.9 | 0.40–1.0 | 0.05–0.25 | ≤0.40 | ≤0.40 | ≤0.10 | ≤0.25 | ≤0.15 | Rem. |
Product Specifications
| Parameter | Description |
|---|---|
| Alloy Grade | 5083 (UNS A95083 / EN AW-5083 / AlMg4.5Mn0.7) |
| Available Tempers | O / H32 / H112 / H116 / H321 |
| Sheet Thickness | 1.5–6 mm |
| Plate Thickness | 6–250 mm |
| Width | 900–2, 650 mm (Customizable up to 3, 100 mm) |
| Length | Standard ≤6, 000 mm; Customizable up to 12, 000 mm |
| Surface Finish | Mill finish / Brushed / Anodized / Tread plate / Embossed plate |
| Protective Film | Blue / Transparent / Black-and-White PE film, 50 μm or 80 μm |
| Executive Standards | ASTM B209 / ASTM B928 / AMS 4056 / QQ-A-250/6 / EN 485 / GB/T 3880 |
Core Properties
Physical Properties
| Parameter | Value | Unit |
|---|---|---|
| Density | 2.66 | g/cm³ |
| Melting Point Range | 574–638 | °C |
| Elastic Modulus | 70.3 | GPa |
| Thermal Conductivity | 117 | W/m·K |
| Electrical Conductivity | 29 | % IACS |
| Specific Heat Capacity | 900 | J/kg·K |
| Coefficient of Thermal Expansion (20–100°C) | 23.8 | μm/m·K |
Note: With a density of 2.66 g/cm³, 5083 is about 65% lighter than steel plates of the same size. Every 1 kg of weight reduced in the hull structure directly translates to higher cargo capacity and lower fuel consumption.
Mechanical Properties by Temper (ASTM B209 / B928)
| Temper | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (%) | Brinell Hardness (HB) |
|---|---|---|---|---|
| O | 270–345 | 115–165 | ≥14 | ~65 |
| H112 | ≥275 | ≥125 | ≥12 | ~70 |
| H32 | 275–345 | ≥215 | ≥8 | ~75 |
| H116 | ≥303 | ≥215 | ≥10 | ~80 |
| H321 | ≥303 | ≥215 | ≥10 | ~80 |
Supplementary Data: Fatigue strength ≈ 160 MPa (5×10⁸ cycles, R=−1); Shear strength ≈ 175 MPa (H116); ER5183 weld seam tensile strength ≥275 MPa, approximately 90% of O-temper base metal.
Temper Details & Selection Guide
Quick Selection Comparison
| Temper | Strength | Formability | Corrosion Certification | Typical Applications |
|---|---|---|---|---|
| O | Medium | Best | Standard | LNG tanks, pressure vessel heads |
| H112 | Medium-High | Good | Standard | Tank trucks, pipelines, uncertified structural parts |
| H32 | Higher | Fair | Standard | General industrial structural plates |
| H116 | High | Fair | ASTM B928 Mandatory | Hulls, decks, polar ships, offshore platforms |
| H321 | High | Fair | ASTM B928 Mandatory | Thick armor, heavy structures, pressure hulls |
5083-H116 Aluminum Plate
Mandatory Standard Temper for Shipbuilding
H116 is a mandatory temper specially formulated for marine environments by ASTM B928. It must pass two corrosion tests: ASTM G66 and ASTM G67.
Applied in hull shell plates, keels, polar icebreaker decks, and offshore drilling platforms.
5083-H321 Aluminum Plate
First Choice for Heavy-Duty Thick Plates
The thermal stabilization temperature of H321 is higher than that of H116, resulting in a more uniform microstructure inside thick cross-sections. It covers thick plate specifications up to 250 mm and also passes ASTM B928 certification.
Applied in naval armor plates, ore carrier bottom plates, and manned submersible pressure hulls.
5083-O Aluminum Plate
The Only Choice for Cryogenic Applications
With an elongation of ≥14%, it maintains complete ductility and fracture toughness at −196°C without low-temperature brittle fracture.
The preferred material for LNG storage tanks (service at −162°C), complying with EN 13445 and ASME Section VIII standards.
5083-H112 Aluminum Plate
Cost-Effective Option
Delivered in the as-fabricated condition after rolling, requiring no additional heat treatment. Processing costs are about 15% lower than H116.
Under the premise of UTS ≥275 MPa and Yield ≥125 MPa, it is suitable for general structural applications without classification society certification requirements.
Main Application Areas
- Shipbuilding & Offshore Engineering: Hull structures have the most stringent requirements for aluminum plates. H116 and H321, certified by ASTM B928, are standard materials for hull shells, keels, polar icebreakers, and offshore drilling platforms.
- LNG & Cryogenic Pressure Vessels: 5083-O is the designated material for LNG storage tanks (service temperature −162°C) and is equally suitable for cryogenic liquid storage and transport equipment (liquid oxygen, nitrogen, argon) and pressure vessel formed heads. Complies with EN 13445 and ASME Section VIII.
- Defense & Armor: 5083-H321 is widely adopted in MIL specifications. Suitable for armored vehicle body plates, naval vessel superstructures, and manned submersible pressure hulls — facing the dual test of extreme water pressure and seawater corrosion.
- Transportation: Dump truck bodies, ore carrier bottom plates, railway passenger car bodies, and liquid chemical tank trucks — high strength and weight reduction are the core demands, and 5083 simultaneously meets weldability and chemical corrosion resistance requirements.
- Industrial Manufacturing: Offshore oil platform structural components, chemical equipment liners, automated equipment base plates, and fixtures — salt spray resistance, acid/alkali resistance, and dimensional stability are the main reasons for selection.
Corrosion Resistance & Weldability
Corrosion Resistance
5083 has the strongest seawater corrosion resistance among all common structural aluminum alloys. Bare 5083-H116 can resist seawater corrosion, but most classification society codes require the use of epoxy anti-corrosion coatings and zinc-aluminum sacrificial anodes below the waterline. This is an engineering code requirement, not a material defect.
Weldability
| Parameter | Recommended Solution |
|---|---|
| Welding Process | TIG (thin plate / high precision) / MIG (thick plate / high efficiency) |
| Recommended Filler Wire | ER5183 (first choice, weld seam ≥275 MPa) / ER5356 (alternative) |
| Shielding Gas | 100% Argon (TIG) / Argon-Helium mixture (MIG for thick plates) |
| Preheating Requirements | Thickness <8 mm: No preheat; >8 mm: Preheat to 80–120°C |
| Interpass Temperature | ≤120°C |
| Post-Weld Heat Treatment | Not required |
Critical Step
Before welding, the groove oxide film MUST be removed with a stainless steel wire brush. Carbon steel wire brushes are strictly prohibited (iron contamination causes corrosion). Welding must be completed within 4 hours after cleaning.
Brief Comparison with Other Aluminum Alloys
| Comparison Item | 5083 | 5052 | 5086 | 6061 |
|---|---|---|---|---|
| Typical Tensile Strength | 270–350 MPa | 170–285 MPa | 240–310 MPa | 260–310 MPa |
| Seawater Corrosion Resistance | Strongest | Good | Good | Medium |
| Weldability | Excellent | Excellent | Excellent | Good (HAZ softening) |
| Classification Society Cert. | H116/H321 fully covered | None | Partial | None |
| Cryogenic Suitability | Down to −196°C | Limited | Limited | No |
| Relative Cost | Higher | ~30% Lower | Similar | Lower |
| Best Suited For | Hull plates / LNG / Armor | Fuel tanks / Interiors | Auxiliary marine structures | Machined land structures |
Selection Conclusion
If the component directly contacts seawater, requires classification society certification, or operates at cryogenic temperatures → You MUST choose 5083. For non-structural marine interior parts, you can downgrade to 5052 to save costs.
Detailed comparisons available: 5083 vs 5052 / 5083 vs 5086 / 5083 vs 6061
Inventory (Stock)
5083-O Stock Sizes (Imperial)
| Thickness (in) | Available Widths (in) | Available Lengths (in) |
|---|---|---|
| 0.250 to 2.000 | 48 / 60 / 72 / 96 / 120 | 96 / 144 / 190 / 240 / 288 |
Standard: ASTM B209 / ASME SB209. MTR provided with shipment.
5083-H116 Stock Sizes (Imperial)
| Thickness (in) | Executive Standards |
|---|---|
| 0.125 / 0.160 | ASTM B928 |
| 0.190 / 0.197 / 0.236 | ASTM B209 / B928 |
| 0.250 / 0.313 / 0.375 | ASTM B928 / AMS 4056 / QQ-A-250/6 |
| 0.394 / 0.472 / 0.500 | AMS 4056 / QQ-A-250/6 |
| 0.625 / 0.750 / 1.000 | AMS 4056 / QQ-A-250/6 / ASTM B928 |
| 1.375 | ASTM B209 / B928 |
5083-H321 Stock Sizes (Imperial)
| Thickness (in) | Executive Standards |
|---|---|
| 0.125 to 0.250 | ASTM B209 / B928 |
| 0.375 to 4.250 | AMS 4056 / QQ-A-250/6 / ASTM B928 |
All specifications support cut-to-size services. Orders can be placed according to drawings or specific dimension requirements.
Packaging, Lead Time & Pricing
| Item | Description |
|---|---|
| Pallet | ISPM-15 certified fumigated wooden pallets, ≤2 tons per pallet, stackable up to 3 layers |
| Protection | Waterproof PVC film + VCI anti-rust paper + Steel edge protectors |
| Drop Test | Passed 50G drop test, suitable for long-distance ocean freight |
| Container | Clean and dry 20′/40′ standard containers or flat racks |
| Lead Time (Stock) | Approx. 7 working days |
| Lead Time (Custom) | To be confirmed based on specifications and quantity |
| Expedited Service | 72-hour expedited processing available (only 5% surcharge) |
| Shipping Terms | FOB / CIF / DDP |
| Pricing Formula | SMM A00 Aluminum Ingot Price + Fixed Processing Fee (approx. 15% below market average) |
Why Choose Worthwill?
7 Major Marine Certifications
Our H116/H321 plates are fully certified by DNV, ABS, LR, CCS, BV, NK, and KR — covering all mainstream classification society requirements worldwide.
Complete Documentation
Original MTRs included with every batch. Third-party (SGS / TÜV) and ASTM G67 corrosion test reports available upon request.
Extensive Size Range
Thickness from 1.5 mm to 250 mm, widths up to 3, 100 mm. Cut-to-size services available to save your secondary processing costs.
Factory-Direct Pricing
Processing fees ~15% below market average, transparently based on the SMM index. Fast quotes within 24 hours.
Hassle-Free Global Shipping
Flexible terms (FOB / CIF / DDP). We provide ISPM-15 compliant packaging and handle destination customs documents expertly.
FAQ
- Q1: What's the difference between 5083-H116 and H321? Which one for shipbuilding?
- Both share identical high strength and ASTM B928 certification. Simply choose H116 for standard hull plates and decks, and H321 for thick plates (>50mm) and heavy-duty structures.
- Q2: Can 5083 be used for LNG storage tanks?
- Yes. 5083-O is the designated material for LNG tanks (−162°C). It maintains exceptional ductility down to −196°C without brittle fracture, fully complying with ASME and EN standards.
- Q3: What welding wire should be used?
- Choose ER5183 (primary) or ER5356 with 100% Argon gas. Clean grooves exclusively with a stainless steel brush, weld within 4 hours, and skip post-weld heat treatment.
- Q4: Does 5083 need a coating below the waterline?
- While bare 5083 resists seawater excellently, marine codes generally require epoxy coatings and sacrificial anodes below the waterline to maximize structural service life.
- Q5: Can 5083 be anodized?
- Yes, but only for functional purposes (corrosion/wear resistance). The high Mg/Mn content turns the finish dark gray, making it unsuitable for decorative applications.
- Q6: What classification society certifications do you have?
- Our H116 and H321 hold all 7 major certifications: DNV, ABS, LR, CCS, BV, NK, and KR. Original MTRs are included with every shipment.
