Machining
Machines well in T851 and T8511 with carbide tools. The stretched tempers limit distortion in long parts.
Aerospace bar and rod
2219 Aerospace Aluminium Bar and Rod
2219 bar and rod are used for machined aerospace parts that must stay strong at very low or raised temperatures, or that will be welded into an assembly. The alloy keeps useful strength from cryogenic conditions up to roughly 300 °C, and its very low magnesium content makes it one of the few high-strength aluminium alloys that welds reliably. Metline supplies extruded and rolled 2219 bar in T8511, T851, T6 and other tempers to AMS 4162 and ASTM specifications, worldwide.
- Alloy
- 2219 (Al-Cu-Mn)
- Tempers
- T8511, T851, T62, T351
- Forms
- Round, square, hex, flat
- Standards
- AMS 4162 · ASTM B211 · B221
Why engineers specify 2219 bar
2219 contains about 6.3 % copper, more than any other common wrought alloy, plus small additions of manganese, zirconium, vanadium and titanium. It has almost no magnesium, which sets it apart from 2014 and 2024.
That chemistry gives three useful properties. First, the high copper content forms precipitates that remain stable at temperatures where 2024 and 7075 soften, so 2219-T8 parts keep useful strength up to around 250 – 315 °C for limited periods. Second, the alloy becomes stronger and tougher as temperature falls, with no ductile-to-brittle transition, which is why it was chosen for liquid-oxygen and liquid-hydrogen tanks. Third, the low magnesium content and zirconium addition make it resistant to hot cracking, so it can be fusion welded with 2319 filler.
In bar form, 2219 is used for machined fittings, flanges, valve bodies and connectors that join welded tank or duct structures, and for parts operating near engines. Extruded bar to AMS 4162 in the stretched T8511 temper is the most common aerospace product; rolled or cold-finished bar to ASTM B211 is used for smaller diameters and commercial orders.
2219 chemical composition (wt %)
Registered limits for 2219, used by AMS 4162, ASTM B211, B221 and EN 573-3. Zirconium is a deliberate addition of 0.10 – 0.25 %; some published tables list it by mistake as a second zinc line.
| Element | Minimum | Maximum | Role |
|---|---|---|---|
| Silicon (Si) | — | 0.20 | Impurity |
| Iron (Fe) | — | 0.30 | Impurity |
| Copper (Cu) | 5.8 | 6.8 | Main strengthening element; also gives strength at temperature |
| Manganese (Mn) | 0.20 | 0.40 | Grain and recrystallisation control |
| Magnesium (Mg) | — | 0.02 | Kept very low, which is key to weldability |
| Zinc (Zn) | — | 0.10 | Impurity |
| Titanium (Ti) | 0.02 | 0.10 | Grain refiner |
| Vanadium (V) | 0.05 | 0.15 | Improves elevated-temperature strength |
| Zirconium (Zr) | 0.10 | 0.25 | Suppresses recrystallisation, refines weld structure |
| Others, each / total | — | 0.05 / 0.15 | |
| Aluminium (Al) | Remainder | About 91.5 – 93.8 % |
Mechanical properties of 2219 bar
| Temper | Tensile strength (typ.) | Yield strength (typ.) | Elongation (typ.) |
|---|---|---|---|
| O | 172 MPa / 25 ksi | 76 MPa / 11 ksi | 18 % |
| T31 / T351 | 360 MPa / 52 ksi | 250 MPa / 36 ksi | 17 % |
| T37 | 395 MPa / 57 ksi | 315 MPa / 46 ksi | 11 % |
| T62 | 415 MPa / 60 ksi | 290 MPa / 42 ksi | 10 % |
| T81 / T851 / T8511 | 455 MPa / 66 ksi | 350 MPa / 51 ksi | 10 % |
| T87 | 475 MPa / 69 ksi | 395 MPa / 57 ksi | 10 % |
Typical values from Aluminum Association and ASM data. Specified minimums depend on product form, thickness and test direction, and are shown in the governing ASTM or AMS document and on the mill certificate.
For guidance, the specified minimums for 2219-T8511 extruded bar are about 400 MPa (58 ksi) tensile and 290 MPa (42 ksi) yield with 6 % elongation in the longitudinal direction, with lower values in the transverse direction. T62 is obtained when the user solution treats and ages the bar after machining or welding; T8 tempers need cold work before ageing and are therefore supplied by the mill.
Physical properties of 2219
- Density
- 2.84 g/cm³ (0.103 lb/in³)
- Modulus of elasticity
- About 73 GPa
- Thermal conductivity
- About 121 W/m·K (T81, T87); about 170 W/m·K (O)
- Electrical conductivity
- About 28 – 30 % IACS (T8 tempers)
- Thermal expansion
- About 22.3 µm/m·°C (20 – 100 °C)
- Melting range
- About 543 – 643 °C
Specifications for 2219 bar and rod
| Document | Scope |
|---|---|
| SAE AMS 4162 | 2219-T8511 extruded bar, rod, wire, profiles and tube up to about 76 mm (2.999 in) least dimension |
| ASTM B211 | Rolled or cold-finished bar, rod and wire; includes 2219 in T851 and other tempers |
| ASTM B221 | Extruded bar, rod, wire, profiles and tube; includes 2219 in O, T31, T3511, T62, T81, T8511 and related tempers |
| UNS | A92219 |
| European | EN AW-2219 (AlCu6Mn) |
| Welding filler | 2319 (AWS ER2319) |
Sizes, tolerances and inspection
Typical supply range
- Round bar
- Small drawn diameters up to large extruded rod; larger sizes as forged bar
- Other shapes
- Square, hexagonal and flat bar; profiles to drawing
- Length
- Random mill lengths, typically 2.5 – 6 m, or cut pieces
- Tolerances
- ASTM B211 / B221 and ANSI H35.2, or EN 754 / EN 755 for European orders
- Inspection
- Dimensional, conductivity and hardness checks; ultrasonic inspection to AMS-STD-2154 when required
Weight of round 2219 bar in kg per metre is about 0.00223 × d², where d is the diameter in mm. A 50 mm bar weighs about 5.6 kg/m and a 100 mm bar about 22.3 kg/m.
Machining, welding and finishing
Welding
GTAW, GMAW, plasma and friction stir welding are all used. Use 2319 filler, clean the joint thoroughly and expect the weld zone to drop well below parent strength unless re-heat-treated to T6x.
Heat treatment after welding
Solution treating and ageing a welded assembly to T62 recovers much of the strength; plan for the distortion this causes.
Finishing
Anodise or conversion coat and prime. 2219 is a copper-rich alloy and is not resistant to seawater without protection.
Typical uses of 2219 bar
- Flanges, bosses and fittings welded into cryogenic propellant tanks
- Valve bodies and connectors for liquid-oxygen and liquid-hydrogen systems
- Brackets and fittings near engines and hot air ducts
- Machined parts for missiles and launch vehicles
- Welded ground-support and test fixtures
| Property | 2219-T851 | 2024-T351 | 2014-T651 | 2618-T61 |
|---|---|---|---|---|
| Typical yield | about 350 MPa | about 325 MPa | about 415 MPa | about 370 MPa |
| Weldability | Good | Poor | Poor–fair | Poor |
| Cryogenic toughness | Excellent | Good | Good | Good |
| Strength at 200 – 300 °C | Good | Fair | Fair | Very good |
How to order 2219 bar
- SpecifyShape and size, temper (e.g. 2219-T8511), length, quantity and specification (AMS 4162, ASTM B211 or B221), plus any ultrasonic class.
- Confirm the specificationWe check the order against the governing AMS, ASTM or EN document, confirm tempers, sizes, tolerances and any customer flow-down clauses, and quote on EXW, FOB, CIF or DAP terms.
- ProcessBars are cut to length, end-marked with alloy, temper and lot, and inspected before packing.
- DocumentEach lot ships with a mill test certificate to EN 10204 3.1 showing heat or lot number, chemical analysis and mechanical test results, plus any ultrasonic or other inspection reports called for on the order.
- Pack and shipMaterial is protected against moisture and handling damage, packed in seaworthy cases or on pallets, marked for traceability and shipped by sea or air.
References and standards
- SAE AMS 4162 – Aluminum Alloy Extrusions, 2219-T8511
- ASTM B211 – Aluminum and Aluminum-Alloy Rolled or Cold-Finished Bar, Rod, and Wire
- ASTM B221 – Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits
2219 aerospace aluminium (aluminum) bar: FAQ
Is 2219 aluminium weldable?
Yes. Its very low magnesium content and zirconium addition make it resistant to hot cracking. Weld with 2319 filler; strength in the weld zone is lower unless the assembly is re-heat-treated.
What is the difference between 2219-T851 and T8511?
Both are solution treated, stretched and artificially aged. T851 applies to rolled bar and plate; T8511 applies to extrusions and allows minor straightening after stretching.
How hot can 2219 parts run?
The alloy retains useful strength to roughly 250 – 315 °C for limited exposures, better than 2024 or 7075. Check the allowables for your time at temperature.
Why is 2219 used for cryogenic tanks?
Its strength and toughness increase as temperature falls, and it can be welded into large tanks, a combination few high-strength aluminium alloys offer.
What is the density of 2219?
About 2.84 g/cm³, slightly higher than 2024 because of the higher copper content.
Need 2219 bar or rod?
Send the size, temper, quantity and specification. We will confirm availability and certification.
