5083 Aluminum Flat Bar
5083 aluminum alloy flat bar is a high-performance aluminum material with magnesium as the main alloying element, specially designed for harsh environments. It is widely used in shipbuilding, pressure vessels, rail transportation, and cryogenic engineering.
5083 aluminum flat bar is a high-strength, non-heat-treatable aluminum-magnesium alloy known for its excellent corrosion resistance, weldability, and performance under extreme conditions. Its nominal chemical composition includes 4.0–4.9% magnesium, 0.15% chromium, up to 0.7% manganese, and trace amounts of other elements. These elements together provide excellent seawater resistance and strength retention after welding.
In typical tempers such as H111, H116, and H321, it exhibits good ductility, making it an ideal choice for demanding structural, marine, automotive, and aerospace applications.
5083 aluminum is widely used in flat bar, sheet, and plate products that conform to ASTM B209/ASME SB209 standards. It is easy to form, machine, and weld, and maintains integrity at temperatures up to 65°C.
5083 Aluminum Flat Bar Chemical Composition
5083 Aluminum Flat Bar Alloying Elements
5083 is primarily composed of magnesium (4.0–4.9%), which provides high strength and work hardening capability. Chromium (0.05–0.25%) and manganese (0.4–1.0%) help refine the grain structure and further enhance corrosion resistance, while the contents of silicon, iron, and zinc are kept to a minimum (<0.4%) to maintain toughness.
5083 Aluminum Flat Bar Specification Ranges
- Mg: 4.0 – 4.9 %
- Cr: 0.05 – 0.25 %
- Mn: 0.4 – 1.0 %
- Si, Fe, Cu, Zn, Ti: each ≤ 0.4 %
- Al: Balance
5083 Aluminum Flat Bar Mechanical Properties
5083 Aluminum Flat Bar Tensile and Yield Strength
In the H321 temper (strain-hardened and stabilized), the ultimate tensile strength of 5083 Aluminum Flat Bar is approximately 300 MPa (43 ksi), with a yield strength close to 215 MPa (31 ksi), making it one of the strongest non-heat-treatable aluminum alloys.
5083 Aluminum Flat Bar Hardness
The Brinell hardness of 5083-H116 and H321 is approximately 83–85 HB, achieving a balance between strength and ductility, suitable for heavy-duty structural applications.
5083 Aluminum Flat Bar Physical Properties
- Density: 2.66 g/cm³
- Thermal Conductivity: 816 BTU·in/hr·ft²·°F
- Electrical Conductivity: ~29 % IACS
- Melting Point: 1, 080 – 1, 180 °F
5083 Aluminum Flat Bar Features
- Corrosion Resistance: Excellent, especially suitable for marine/saltwater environments due to its magnesium content. Also resistant to industrial chemicals and atmospheric conditions.
- Strength: High tensile and yield strength, retains performance at low temperatures (ideal for cryogenic applications).
- Weldability: Good; commonly welded using TIG, MIG, or resistance welding. Maintains high post-weld strength.
- Non-Heat-Treatable: Strengthened through strain hardening (cold working).
- Density: Approximately 2.66 g/cm³ (lightweight).
- Thermal/Electrical Conductivity: Moderate; not typically used for conductive applications.
5083 Aluminum Flat Bar Dimensions and Specifications
| Parameter | Range |
| Thickness (mm) | 3 mm – 150 mm |
| Width (mm) | 10 mm – 600 mm |
| Shape | Rectangular cross-section |
| Temper | H111 (annealed), H116 (stabilized), and H321 (strain-hardened) |
| Alloy Grade | 5083 Aluminum Alloy |
| Features | High strength, corrosion resistance, good weldability |
| Standards | ASTM B209/ASME SB209: Sheet and plate |
| EN AW-5083: European standard | |
| ISO 6361: International standard for wrought flat products | |
| Surface Finish | Mill Finish: Rough, non-uniform surface. |
| Anodized: Improved aesthetics/corrosion resistance. | |
| Painted/Powder-Coated: For specific environmental protection. |
5083 Aluminum Flat Bar Tempers
Available in strain-hardened tempers such as:
H111: Slight work hardening, annealed for formability.
H116/H321: Optimized for marine environments; improved resistance to exfoliation corrosion.
Corrosion Resistance of 5083 Aluminum Flat Bar
5083 has excellent resistance to seawater and industrial chemical corrosion, performing better in marine environments than most other non-heat-treatable alloys. Even after welding, its corrosion resistance remains outstanding, whereas many aluminum alloys suffer strength loss after welding.
Manufacturing and Welding of 5083 Aluminum Flat Bar
5083 Aluminum Flat Bar is easy to cold work and can be produced in various H temper states, with minimal springback during forming or bending. It has excellent weldability using standard welding methods (GMAW, GTAW), and welded joints can retain over 90% of the base metal strength.
Applications of 5083 Aluminum Flat Bar
Marine Applications of 5083 Aluminum Flat Bar
5083 Aluminum Flat Bar is widely used for hull plating, decks, superstructures, and underwater fittings. It resists pitting corrosion and stress corrosion cracking in seawater.
| Application Area | Description |
| Hull Plating | 5083 Aluminum Flat Bar is widely used in hull structures due to its excellent corrosion resistance and good weldability. It has high strength and outstanding resistance to seawater corrosion, maintaining structural integrity even in highly humid and saline marine environments. Its good rigidity and flatness ensure hull shape precision and overall compressive strength, providing better durability and longer service life for vessels. |
| Ship Decks | 5083 Aluminum Flat Bar is one of the ideal materials for constructing ship decks. It not only provides sufficient load-bearing capacity to support machinery and personnel on the deck, but also has good corrosion resistance to withstand erosion from wind, rain, and wave impact. Its excellent formability and surface treatment compatibility make deck structures easy to process and maintain, suitable for various types of offshore working vessels and military ships. |
| Ship Superstructures | 5083 Aluminum Flat Bar is widely used in the construction of ship superstructures such as cockpits, communication towers, and living quarters. Its lightweight and high-strength characteristics help effectively reduce the vessel's center of gravity, improving stability and navigation performance. Additionally, its excellent corrosion resistance ensures that the upper structure retains its strength even after long exposure to salt spray environments, reducing maintenance frequency and cost. |
| Underwater Fittings | 5083 Aluminum Flat Bar performs excellently in the manufacture of underwater fittings (such as submersible brackets, propeller guards, and underwater instrument mounts). It offers high resistance to pitting caused by chlorides in seawater and can avoid stress corrosion cracking in frequently pressure-varying deep-sea environments. This flat bar alloy also provides good machinability, allowing precise fabrication of complex underwater structural components for long-term reliable operation. |
What Other Fields Does 5083 Aluminum Flat Bar Apply To?
- Transportation: truck trailers, railway vehicles, aircraft components.
- Construction: bridges, pressure vessels, chemical storage tanks.
- Cryogenics: LNG storage, low-temperature components.
Advantages and Limitations of 5083 Aluminum Flat Bar
- Advantages: High strength, excellent corrosion resistance, excellent weldability, good formability in H temper states.
- Limitations: Non-heat treatable; avoid prolonged exposure to temperatures above 65°C (150°F) to prevent sensitization of magnesium; moderate machinability.
Manufacturing Considerations for 5083 Aluminum Flat Bar
- Machining: May be sticky; use sharp tools and lubricants.
- Forming: Excellent ductility in annealed (O) temper; moderate hardness in high-temperature tempers.
- Welding: For high-temperature applications, avoid using 5xxx alloys with magnesium content >3% (risk of sensitization).
Comparison Between 5083 Aluminum and Other Alloys
- Compared with 6061 (6xxx series): 5083 offers better corrosion resistance and weldability, but has lower machinability.
- Compared with 5052: Higher strength and better performance in harsh environments.
