2219-O
Fully annealed for forming. Parts are spun, stretched or bent and then heat treated by the user, usually to T62. AMS 4031 covers O sheet and plate.
Weldable high-strength aerospace plate
2219 Aerospace Aluminium Sheet and Plate
2219 sheet and plate are the established material for welded high-strength aerospace structures, above all cryogenic propellant tanks, because the alloy welds reliably and keeps its strength and toughness from about −253 °C up to roughly 300 °C. It is supplied bare or Alclad in tempers from annealed O to the high-strength T851 and T87. Metline supplies 2219 sheet and plate to AMS 4031, ASTM B209 and customer specifications, cut to size and certified, to aerospace, space and defence buyers worldwide.
- Alloy
- 2219 (Al-Cu-Mn-Zr-V)
- Tempers
- O, T31, T37, T62, T81, T851, T87
- Range
- Sheet and plate, bare or Alclad
- Standards
- AMS 4031 · ASTM B209
What makes 2219 plate special
Most high-strength aluminium alloys are difficult or impossible to fusion weld. 2219 is the exception among the high-copper alloys: with about 6.3 % copper, almost no magnesium and a zirconium addition, it resists hot cracking and can be welded into large, pressure-tight structures.
The alloy was developed in the 1950s and found its defining use in rocketry. Large launch-vehicle propellant tanks, including those of the Saturn V stages and the original Space Shuttle external tank, were welded from 2219 plate. The same reasoning still applies: 2219 is strong, its toughness rises rather than falls at cryogenic temperatures, it welds with well-understood procedures, and it is available in thick, wide plate for machined and formed tank panels.
At the other end of the temperature range, 2219 resists softening better than 2024 and much better than 7075. Its copper-rich precipitates are stable up to roughly 250 – 315 °C for limited exposures, so the alloy is also chosen for supersonic aircraft skins, engine-area structure and parts that see heat during service or processing.
The price of these advantages is moderate room-temperature strength and limited corrosion resistance. 2219-T87 is weaker than 7075-T6 or 2024-T3 in tension, and like all high-copper alloys it needs anodising, conversion coating or Alclad cladding. Third-generation aluminium-lithium alloys such as 2195 have replaced 2219 in some new tank designs because they save weight, but 2219 remains widely specified for its proven weldability, availability and lower cost.
2219 chemical composition (wt %)
These are the registered limits for alloy 2219, followed by AMS 4031, ASTM B209 and EN 573-3. Alclad 2219 is clad on both faces with alloy 7072, a zinc-bearing alloy that is anodic to the core and protects it sacrificially.
| 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 % |
Each minor element has a purpose. Manganese and zirconium form fine dispersoids that keep the grain structure unrecrystallised and refine the weld fusion zone. Vanadium and titanium further stabilise the structure at temperature. The tight magnesium limit (0.02 % max.) is critical: even small amounts of magnesium increase hot-cracking sensitivity during welding.
Mechanical properties of 2219 sheet and plate by temper
Typical values below apply to bare sheet and plate in the longitudinal direction. Alclad sheet is slightly weaker because the 7072 cladding carries little load. Specified minimums in ASTM B209 and the AMS documents are lower than typical values and decrease in thick plate.
| 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.
The T8 tempers (T81, T851, T87) differ from T6-type tempers in that the material is cold worked, by stretching or rolling, between quenching and ageing. The cold work speeds up and refines precipitation, giving higher yield strength and better resistance to stress corrosion. T87, with about 7 % cold work, is the strongest standard temper; T851 is stretched only 1.5 – 3 % for stress relief and is preferred for plate that will be heavily machined.
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
Performance from cryogenic to elevated temperatures
2219 is often described as a "wide temperature range" alloy, and the description is accurate. Aluminium alloys with a face-centred cubic structure have no ductile-to-brittle transition, but 2219 goes further: its tensile strength, yield strength and fracture toughness all increase as it is cooled towards liquid-hydrogen temperature (about −253 °C), and its weld joints keep useful toughness too.
| Temperature range | Behaviour of 2219-T8 plate | Design implication |
|---|---|---|
| −253 °C to −196 °C (LH2, LN2) | Strength and toughness higher than at room temperature | Suitable for liquid hydrogen and oxygen tanks and lines |
| −50 °C to 100 °C | Normal room-temperature properties | Standard airframe design data apply |
| 100 °C to 200 °C | Gradual strength reduction; better retention than 2024 and 7075 | Check allowables for time at temperature |
| 200 °C to about 315 °C | Useful strength for limited exposures; over-ageing with long exposure | Engine-area and short-duration heated parts |
For design numbers at temperature, use MMPDS or the producer's data for the exact temper and exposure time; the values depend strongly on how long the part stays hot.
2219 tempers explained
2219-T31 / T351
Solution heat-treated, cold worked and naturally aged. Used as the starting temper for parts that will be formed and then artificially aged to T81 or T851.
2219-T37
Solution heat-treated with about 7 % cold work and naturally aged. Precursor to T87.
2219-T62
Solution heat-treated and artificially aged by the user, often after forming or welding. No cold work, so yield strength is lower than T81.
2219-T81 / T851
Solution heat-treated, stretched or cold worked, then artificially aged. T851 is stretched for stress relief and is the usual choice for machined plate.
2219-T87
Solution heat-treated, cold worked about 7 % and artificially aged. Highest strength; widely used for welded tank plate.
Specifications and equivalents
2219 sheet and plate are ordered against aerospace (AMS), ASTM or European documents. The specification fixes the temper, thickness range, test directions and inspection, so it should be stated on every enquiry.
| Document | Scope |
|---|---|
| SAE AMS 4031 | 2219 sheet and plate, annealed (O) or as-fabricated when specified, about 0.5 – 50.8 mm |
| ASTM B209 / ASME SB-209 | General sheet and plate specification; covers bare and Alclad 2219 in O, T31, T351, T37, T62, T81, T851 and T87 |
| AMS-QQ-A-250/30 | Former federal specification for bare 2219 sheet and plate, still found on many drawings |
| AMS Alclad documents | Separate AMS specifications cover Alclad 2219 sheet in specific tempers; send the number on your drawing |
| UNS | A92219 |
| European | EN AW-2219 (AlCu6Mn) |
| Welding filler | 2319 (AWS ER2319) |
Bare or Alclad 2219?
Bare 2219 is the alloy as rolled and heat treated, with no cladding. It is the normal form for plate over a few millimetres, for parts machined on all surfaces, and for welded structures, because cladding would be removed by machining or mixed into the weld.
Bare plate relies on anodising, chemical conversion coating and paint for corrosion protection.
Alclad 2219 has a thin layer of 7072 alloy bonded to each face during rolling. The cladding corrodes preferentially and protects the copper-rich core, even at scratches and cut edges.
It is mainly used for thin sheet skins exposed to the atmosphere. Strength is a little lower than bare sheet, and the cladding must be accounted for in fatigue and weld design.
Sizes and weights of 2219 sheet and plate
Typical supply range
- Sheet
- About 0.5 – 6 mm, bare or Alclad
- Plate
- About 6 – 150 mm; heavier sections by agreement
- Width and length
- Common sizes such as 1250 × 2500 mm and 1500 × 3000 mm; wider and longer plate and cut blanks on request
- Imperial sizes
- 48 × 144 in and 60 × 144 in sheets; plate in inch thicknesses
- Processing
- Saw cutting, waterjet profiling and cut-to-size blanks
Wide, thick 2219 plate for tank panels is produced in mill campaigns, so share your size requirements early.
2219 is denser than most aluminium alloys at 2.84 g/cm³, so a plate weighs 2.84 kg per square metre for each millimetre of thickness. The table gives quick reference weights; for other sizes use the plate weight calculator with a density of 2.84.
| Thickness (mm) | kg per m² | 1250 × 2500 mm (kg) | 1500 × 3000 mm (kg) |
|---|---|---|---|
| 1 | 2.8 | 8.9 | 12.8 |
| 2 | 5.7 | 17.8 | 25.6 |
| 3 | 8.5 | 26.6 | 38.3 |
| 5 | 14.2 | 44.4 | 63.9 |
| 6 | 17.0 | 53.2 | 76.7 |
| 8 | 22.7 | 71.0 | 102.2 |
| 10 | 28.4 | 88.8 | 127.8 |
| 12 | 34.1 | 106.5 | 153.4 |
| 16 | 45.4 | 142.0 | 204.5 |
| 20 | 56.8 | 177.5 | 255.6 |
| 25 | 71.0 | 221.9 | 319.5 |
| 30 | 85.2 | 266.2 | 383.4 |
| 40 | 113.6 | 355.0 | 511.2 |
| 50 | 142.0 | 443.8 | 639.0 |
| 60 | 170.4 | 532.5 | 766.8 |
| 80 | 227.2 | 710.0 | 1022.4 |
| 100 | 284.0 | 887.5 | 1278.0 |
| 150 | 426.0 | 1331.2 | 1917.0 |
Tolerances, inspection and certification
Quality requirements
- Dimensional tolerances
- ANSI H35.2 / ASTM B209 tables for ASTM and AMS orders; EN 485-3 and EN 485-4 for European orders
- Flatness
- Per the standard; T851 plate is stretched for flatness and low residual stress
- Ultrasonic inspection
- To AMS-STD-2154 or ASTM B594 at the class specified, usually for plate over 12.7 mm
- Mechanical tests
- Tensile tests in the directions required by the specification; conductivity and hardness checks
- Certification
- EN 10204 3.1 mill certificate with lot traceability, chemistry and mechanical results
For welded tank plate, many programmes add their own requirements: weld qualification coupons from the same lot, cleanliness and surface condition limits, and restrictions on surface defects that could open up during forming. List these flow-down clauses on the enquiry so they are included in the quotation.
Welding, forming and machining 2219
Fusion welding
Gas tungsten arc, gas metal arc, variable-polarity plasma arc and electron beam welding are all used. Filler alloy 2319 (2219 chemistry with added titanium and vanadium for weld grain refinement) is standard.
Friction stir welding
Solid-state friction stir welding avoids melting, porosity and hot cracking, and gives higher joint strength than fusion welding. It is now common on large tank barrels and domes.
Weld preparation
Remove oxide and contamination immediately before welding: degrease, then mechanically or chemically clean. Hydrogen from moisture and hydrocarbons is the main cause of porosity.
Joint strength
The weld and heat-affected zone are weaker than T87 parent plate. Designs either accept as-welded allowables or heat treat the welded assembly to T62.
Forming
Form tank gores and panels in O or T31/T37, then age. Brake forming of T8 tempers requires generous bend radii.
Machining
Machines cleanly with carbide tools; T851 plate keeps flat when large pockets are milled.
Where 2219 sheet and plate are used
- Launch vehicles: welded liquid-oxygen and liquid-hydrogen tank barrels, domes and rings
- Spacecraft: pressure vessels, propellant tanks and welded structures
- Aircraft: skins and structure in warm zones, supersonic airframe parts and engine-area fittings
- Defence: welded structures and armour-related applications needing strength and weldability
- Cryogenic engineering: industrial cryogenic vessels and test equipment
- High-temperature tooling: fixtures and parts that must keep strength in heated processes
A typical example is a cryogenic tank barrel: 2219-T87 plate is machined into thin isogrid-stiffened panels, formed to the barrel radius, and joined by friction stir or plasma arc welding with 2319 filler.
2219 compared with alternative alloys
| Property | 2219-T87 | 2195-T8 (Al-Li) | 2024-T351 | 7075-T651 | 5083-H321 |
|---|---|---|---|---|---|
| Typical yield strength | about 395 MPa | about 500 MPa or more | about 325 MPa | about 505 MPa | about 230 MPa |
| Density | 2.84 g/cm³ | about 2.71 g/cm³ | 2.78 g/cm³ | 2.81 g/cm³ | 2.66 g/cm³ |
| Fusion weldability | Good | Fair (FSW preferred) | Poor | Poor | Excellent |
| Cryogenic toughness | Excellent | Very good | Good | Fair | Excellent |
| Strength at 200 °C | Good | Fair | Fair | Poor | Low |
| Relative cost | Medium | High | Medium | Medium | Low |
Choose 2219 when weldability and a wide temperature range matter together. 2195 saves weight in tanks at higher material cost; 5083 is cheaper and very weldable but much weaker; 2024 and 7075 are stronger at room temperature but are not used for fusion-welded structure.
How to order 2219 sheet and plate
- SpecifyTemper (e.g. 2219-T87 or T851), bare or Alclad, thickness, width, length or cut size, quantity, specification and revision, ultrasonic class and any weld-qualification requirements.
- 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.
- ProcessPlates are cut, protected with film or interleaving, inspected for dimensions, flatness and surface, and ultrasonically tested where specified.
- 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 4031 – Aluminum Alloy Sheet and Plate, 2219-O
- ASTM B209 – Standard Specification for Aluminum and Aluminum-Alloy Sheet and Plate
- AWS A5.10 – Welding Consumables: Wires and Rods for Aluminum and Aluminum-Alloys (ER2319)
- AMS-STD-2154 – Inspection, Ultrasonic, Wrought Metals
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits
2219 aerospace aluminium (aluminum) plate: frequently asked questions
Why is 2219 used for rocket propellant tanks?
It combines moderate-to-high strength with reliable weldability and strength and toughness that increase at liquid-hydrogen and liquid-oxygen temperatures.
Which filler should be used to weld 2219?
2319 filler (AWS ER2319) is standard. It matches the parent chemistry and adds titanium and vanadium to refine the weld structure. Friction stir welding needs no filler.
What is the difference between 2219-T851 and T87?
Both are cold worked before artificial ageing. T851 is stretched 1.5 – 3 % for stress relief; T87 receives about 7 % cold work and is stronger.
Is 2219 plate corrosion resistant?
Not on its own. It is a copper-rich alloy that should be anodised, conversion coated and painted, or supplied as Alclad sheet for external skins.
How much does 2219 plate weigh?
2.84 kg per m² per millimetre of thickness. A 1250 × 2500 × 10 mm plate weighs about 88.8 kg.
Can 2219 be heat treated after welding?
Yes. Welded assemblies can be solution treated and aged to T62 to recover strength, but the process causes distortion that must be planned for.
Do you supply 2219 plate with ultrasonic testing?
Yes, to AMS-STD-2154 or ASTM B594 at the class on your order, with the inspection report included.
Need 2219 sheet or plate?
Send temper, thickness, size, quantity and specification. Our team will confirm availability, inspection and a delivered price.
