Superior Corrosion Resistance • Excellent Weldability • Marine Environment Proven
5083-H321 is the premier marine-grade aluminum alloy, offering exceptional corrosion resistance in saltwater environments combined with high strength and excellent weldability. This magnesium-based alloy is the material of choice for shipbuilding, offshore structures, pressure vessels, and critical marine applications where durability in harsh environments is essential.
5083-H321 is a non-heat-treatable aluminum-magnesium alloy that achieves its strength through strain hardening. The H321 temper indicates the material has been strain hardened and stabilized to prevent stress corrosion cracking in marine environments. With the highest strength of the non-heat-treatable aluminum alloys, it combines excellent corrosion resistance, superior weldability, and good formability for demanding marine and industrial applications.
5083-H321 is the go-to material for marine applications because it combines high strength with superior resistance to seawater corrosion. The stabilized H321 temper specifically addresses the risk of stress corrosion cracking in marine service, making it ideal for boat hulls, superstructures, offshore platforms, and other critical marine structures.
| Element | Weight % | Purpose |
|---|---|---|
| Magnesium (Mg) | 4.0 - 4.9 | Primary strengthening and corrosion resistance |
| Manganese (Mn) | 0.40 - 1.0 | Grain refinement and strength enhancement |
| Chromium (Cr) | 0.05 - 0.25 | Controls grain structure and prevents recrystallization |
| Iron (Fe) | ≤ 0.40 | Impurity element |
| Silicon (Si) | ≤ 0.40 | Impurity element |
| Copper (Cu) | ≤ 0.10 | Kept low for corrosion resistance |
| Zinc (Zn) | ≤ 0.25 | Minor alloying element |
| Titanium (Ti) | ≤ 0.15 | Grain refinement |
| Aluminum (Al) | Balance (93.2-95.6) | Base metal |
Chemistry Note: The high magnesium content provides both strength and exceptional corrosion resistance. Low copper content ensures maximum resistance to stress corrosion cracking in marine environments.
| Property | Metric | Imperial |
|---|---|---|
| Tensile Strength (Ultimate) | 317 MPa | 46,000 psi |
| Yield Strength | 228 MPa | 33,000 psi |
| Elongation at Break | 16% (in 50mm) | |
| Modulus of Elasticity | 70.3 GPa | 10.2 × 10⁶ psi |
| Brinell Hardness | 85 HB | |
| Shear Strength | 186 MPa | 27,000 psi |
| Fatigue Strength (500M cycles) | 159 MPa | 23,000 psi |
| Shear Modulus | 26.2 GPa | 3.8 × 10⁶ psi |
Note: H321 temper provides strain hardened strength with stabilization treatment to prevent stress corrosion cracking. Properties are typical for plate form.
Ship hulls, superstructures, deck plating, bulkheads, masts, offshore drilling platforms, patrol boats, yachts, sailboats, and all marine structures requiring high corrosion resistance in saltwater environments.
Cryogenic tanks for LNG transport, pressure vessels, storage tanks, unfired welded pressure vessels, and containers requiring excellent low-temperature toughness and weldability.
Truck and trailer bodies, tanker trucks, railway cars, automotive body panels, and mass transit vehicles where corrosion resistance and weldability are important.
Architectural panels, bridge components, structural members in corrosive environments, armor plating, and heavy-duty structural applications.
Drilling rigs, offshore structures, chemical processing equipment, desalination plants, and industrial equipment exposed to corrosive environments.
| Operation | Recommended Parameters |
|---|---|
| Turning | Speed: 800-1200 SFM (245-365 m/min), Feed: 0.010-0.020 ipr |
| Milling | Speed: 900-1400 SFM (275-425 m/min), Good chip evacuation important |
| Drilling | Speed: 250-400 SFM (75-120 m/min), Use coolant for deep holes |
| Welding (TIG) | 5356 or 5183 filler, AC current, argon shielding |
| Welding (MIG) | 5356 or 5183 wire, argon/helium mix, DC+ polarity |
| Coolant | Soluble oil or synthetic coolants recommended |
Welding Excellence: 5083-H321 is specifically designed for welded structures. The H321 temper's stabilization treatment ensures the weld zone maintains excellent resistance to stress corrosion cracking in marine service.
Get a quote for AS9100D certified 5083-H321 aluminum machining with full material traceability and marine certification.