5083-O
Fully annealed. Maximum ductility and toughness; preferred for cryogenic parts and anything that will be formed.
Aerospace · high-magnesium bar
5083 Aerospace Aluminium Bar & Rod
5083 bar is the strongest non-heat-treatable aluminium bar in common supply, with excellent corrosion resistance, weldability and toughness down to cryogenic temperatures. In aerospace it is used for welded fittings, cryogenic and launch-site hardware, ground support equipment and tooling rather than airframe structure. Metline supplies 5083 round, square, hex and flat bar in O, H111 and H112 to ASTM B221 and EN 755, worldwide.
- Alloy
- 5083 (Al-4.4Mg-0.7Mn)
- Tempers
- O, H111, H112, F
- Diameter
- About 5 – 400 mm
- Standards
- ASTM B221 · EN 755-2 · ISO 6362
The role of 5083 bar in aerospace
5083 contains about 4.4 % magnesium and 0.7 % manganese. It is the strongest of the widely used non-heat-treatable alloys, keeps most of its strength after welding and becomes stronger and tougher as temperature falls, which is why it is a standard cryogenic alloy.
Those properties shape where it is used. 5083 is not an airframe alloy: wings, fuselages and other primary structure use heat-treatable 2xxx and 7xxx grades, and claims that 5083 is used for fuselage or wing structure should be treated with caution. Instead, 5083 bar turns up where welded corrosion-resistant hardware is needed: fittings and flanges for cryogenic propellant and liquid-gas systems at launch sites, machined parts in ground support equipment, aircraft-carrier and coastal flight-line equipment, test fixtures, transport containers and shelters, and tooling that must stay dimensionally stable.
Bar is normally extruded and supplied in the as-extruded H112 condition or annealed (O or H111). Because 5083 is strengthened by cold work, strain-hardened tempers such as H32 are only available in small sections, where the cold-finishing reduction can be applied evenly.
5083 chemical composition (wt %)
| Element | Minimum | Maximum | Role in the alloy |
|---|---|---|---|
| Silicon (Si) | — | 0.40 | Impurity |
| Iron (Fe) | — | 0.40 | Impurity |
| Copper (Cu) | — | 0.10 | Kept low for seawater resistance |
| Manganese (Mn) | 0.40 | 1.0 | Adds strength and refines grain |
| Magnesium (Mg) | 4.0 | 4.9 | Main strengthening element |
| Chromium (Cr) | 0.05 | 0.25 | Grain control, stress-corrosion resistance |
| Zinc (Zn) | — | 0.25 | Impurity |
| Titanium (Ti) | — | 0.15 | Grain refiner in the cast ingot |
| Others, each / total | — | 0.05 / 0.15 | |
| Aluminium (Al) | Remainder | About 92.4 – 95.6 % |
Registered Aluminum Association limits, also used for EN AW-5083 (AlMg4.5Mn0.7) in EN 573-3.
5083 bar mechanical properties
Specified minimums for extruded bar to ASTM B221 are shown first. EN 755-2 values are similar; size limits apply, so check the band for your section on the mill certificate.
| Temper | Tensile strength | Yield strength (0.2 %) | Elongation (min) |
|---|---|---|---|
| O | 270 – 350 MPa (39 – 51 ksi) | ≥ 110 MPa (16 ksi) | About 12 – 14 % |
| H111 | ≥ 275 MPa (40 ksi) | ≥ 165 MPa (24 ksi) | About 12 % |
| H112 | ≥ 270 MPa (39 ksi) | ≥ 110 MPa (16 ksi) | About 12 % |
| F | No limits | No limits | No limits |
| Typical values (O / H112) | Value |
|---|---|
| Tensile strength | About 290 MPa (42 ksi) |
| Yield strength | About 145 MPa (21 ksi) |
| Elongation | About 20 – 22 % |
| Brinell hardness | About 75 HB |
| At −196 °C (O temper) | Tensile strength rises to roughly 400 MPa with elongation maintained |
Physical properties
- Density
- 2.66 g/cm³ (0.096 lb/in³)
- Modulus of elasticity
- 70.3 GPa (10,200 ksi)
- Thermal conductivity
- About 117 – 120 W/m·K
- Electrical conductivity
- About 29 % IACS
- Coefficient of thermal expansion
- 23.8 µm/m·°C (20 – 100 °C)
- Melting range
- 591 – 638 °C
5083 bar tempers
5083-H111
Annealed and lightly strain-hardened by straightening. Slightly higher yield than O with the same corrosion behaviour.
5083-H112
As extruded with guaranteed minimum properties. The most common bar condition for machined parts.
5083-H32 (small sections)
Strain-hardened and stabilised; higher strength, available in limited sizes.
Standards and equivalents
Commercial and aerospace-adjacent orders for 5083 bar are normally written to ASTM B221 or EN 755. Older drawings may cite QQ-A-200/4, the cancelled federal specification for 5083 extrusions. Some published material lists AMS 4156 for 5083 bar; AMS 4156 actually covers 6063-T6 extrusions, so check any such reference on your drawing.
| System | Designation / standard |
|---|---|
| ASTM / ASME | ASTM B221 (ASME SB-221) extruded bar and rod |
| US federal (legacy) | QQ-A-200/4 |
| UNS | A95083 |
| European | EN AW-5083 (AlMg4.5Mn0.7), EN 755-2 |
| German Werkstoff | 3.3547 |
| ISO | AlMg4.5Mn0.7, ISO 6362-2 |
| French (legacy) | AG4.5MC |
5083 bar sizes and weights
Supply range
- Round bar
- About 5 – 400 mm diameter (extruded); smaller sizes cold finished
- Square bar
- About 6.35 – 150 mm
- Hex and flat bar
- Hex to about 100 mm across flats; flats to drawing
- Length
- 1 – 6 m, fixed or random; cut pieces on request
- Surface
- Mill finish; peeled or turned on request
Weight per metre of round bar is π/4 × d² × 2.66 ÷ 1000 kg (d in mm). See the bar weight calculator for other shapes.
| Diameter (mm) | kg per metre | kg per 3 m bar | Diameter (in) |
|---|---|---|---|
| 10 | 0.209 | 0.63 | 0.39 |
| 20 | 0.836 | 2.51 | 0.79 |
| 30 | 1.880 | 5.64 | 1.18 |
| 40 | 3.343 | 10.03 | 1.57 |
| 50 | 5.223 | 15.67 | 1.97 |
| 60 | 7.521 | 22.56 | 2.36 |
| 80 | 13.371 | 40.11 | 3.15 |
| 100 | 20.892 | 62.67 | 3.94 |
| 120 | 30.084 | 90.25 | 4.72 |
| 150 | 47.006 | 141.02 | 5.91 |
| 200 | 83.566 | 250.70 | 7.87 |
| 250 | 130.572 | 391.72 | 9.84 |
| 300 | 188.024 | 564.07 | 11.81 |
Machining, welding and service limits
Machining
Gummy in O; use sharp, polished high-rake tools, high speeds and ample coolant. H112 machines a little cleaner.
Welding
TIG and MIG with ER5183 filler to match strength; ER5356 for lower-stress joints. Weld zones keep close to O-temper strength.
Service temperature
Do not use for long periods above about 65 °C: magnesium-rich phases can form on grain boundaries and cause intergranular and stress corrosion. Use 5454 or 5052 for warm service.
Cryogenic
Strength and toughness improve at low temperature, with no ductile-to-brittle transition, making 5083-O a standard choice for liquid-gas fittings.
Anodising
Takes protective anodising; the finish is greyer than on 6xxx alloys.
Galvanic contact
Isolate from stainless and carbon-fibre parts in wet environments.
Typical applications
- Cryogenic hardware: flanges, valve bodies and fittings for liquid oxygen, nitrogen and natural gas systems at launch and test sites
- Ground support equipment: machined parts for stands, tow equipment and refuelling systems exposed to weather and salt air
- Welded fittings in 5083 plate structures such as containers, shelters and transport cases
- Tooling and fixtures that need stable, weldable aluminium
- Marine and naval aviation equipment on carrier decks and coastal airfields
How to order
- SpecifyAlloy and temper, shape and size, length or cut pieces, quantity and the governing specification with its revision (ASTM B221 or EN 755-2).
- ConfirmWe confirm the specification can be met, the tolerance class, any extra tests and the delivery terms (EXW, FOB, CIF or DAP).
- InspectMaterial is checked for dimensions, straightness and surface condition; tests named on the order are carried out or arranged with a third party.
- DocumentEach lot ships with a mill test certificate to EN 10204 3.1 showing chemistry and mechanical results, traceable to the cast or lot number.
- Pack and shipExport packing in sealed, moisture-protected wooden cases or on pallets, shipped by sea or air to your port or door.
References and standards
- ASTM B221 – Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles and Tubes
- EN 755-2 – Extruded rod/bar, tube and profiles: mechanical properties
- ISO 6362-2 – Wrought aluminium and aluminium alloy extruded rods/bars, tubes and profiles: mechanical properties
- EN 573-3 – Aluminium and aluminium alloys: chemical composition and form of wrought products
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits (Teal Sheets)
- ASM Handbook, Vol. 2 – Properties and Selection: Nonferrous Alloys and Special-Purpose Materials
5083 aerospace aluminium (aluminum) bar: FAQs
Is 5083 used in aircraft structures?
Not in primary airframe structure, which uses heat-treatable 2xxx and 7xxx alloys. 5083 bar is used for welded fittings, cryogenic and launch-site hardware, ground support equipment and tooling.
Why is 5083 good for cryogenic service?
Its strength and toughness increase as temperature falls and it has no ductile-to-brittle transition, so it is widely used for liquid-gas storage and transfer hardware.
What filler is used to weld 5083 bar?
ER5183 is the standard match for strength; ER5356 is acceptable for lower-stress joints.
What is the maximum service temperature for 5083?
Avoid sustained service above about 65 °C, where sensitisation can lead to intergranular and stress-corrosion cracking.
Can 5083 bar be heat treated?
No. It is strengthened by cold work only; heat can anneal it but not age-harden it.
Need 5083 bar for cryogenic or GSE parts?
Send shape, size, temper, specification and quantity. We will reply with availability, certification and a delivered price.
