Aluminum 2124
AA 2124 · UNS A92124 · EN AW-2124, AW 2124
2124 is a high-purity version of 2024 — an Al-Cu-Mg alloy with tightly controlled Fe and Si — developed for thick plate and normally supplied stress-relieved in T851.
2124 tempers and conditions
2124 is supplied in 5 conditions, soft to hard.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for heavy forming or machining prior to solution treatment. | 75 | 185 | 20 | 47 HB | 50 % IACS |
T3, stress relieved by stretching | Naturally aged plate with low residual stress — best choice when machined parts must stay flat and higher toughness/ductility is wanted over peak strength. | 325 | 470 | 15 | 120 HB | 30 % IACS |
Solution heat treated, cold worked and naturally aged | Naturally aged cold-worked condition for thinner rolled product where residual-stress relief by stretching is not specified. | 325 | 470 | 15 | 120 HB | 30 % IACS |
Solution treated, stress relieved by stretching with minor… | Extruded-product equivalent of T851 when 2124 is supplied as bar or profile. | 435 | 480 | 7 | 126 HB | 38 % IACS |
T8, stress relieved by stretching | Standard aerospace/mould plate condition: peak strength with good short-transverse toughness and low residual stress for heavy machining. | 440 | 490 | 8 | 128 HB | 38 % IACS |
What is 2124?
2124 is a high-purity version of 2024 — an Al-Cu-Mg alloy with tightly controlled Fe and Si — developed for thick plate and normally supplied stress-relieved in T851. The cleaner microstructure gives higher short-transverse toughness and better resistance to lamellar tearing than standard 2024 plate, so it is machined into airframe frames, ribs, bulkheads and tooling plate serving up to about 150 °C. Corrosion resistance is poor and needs cladding or anodize plus primer, fusion welding is not recommended, and cost is above common grades; 2024-T351 plate is the cheaper alternative. 2124 has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 502°C (936 °F). 2124 has a yield strength of 440 MPa (63.8 ksi) and a tensile strength of 490 MPa (71.1 ksi) — stronger than 91% of aluminum grades. Elongation at break is 8% and the elastic modulus is 73.1 GPa (10.6 Msi).
What is 2124 used for?
- Aerospace plate
- Bulkheads
- Wing skins
Advantages
- High strength — 440 MPa (63.8 ksi), better than 91% of aluminum grades
- Tough — resists crack growth — 34 MPa·√m (30.9 ksi·√in), better than 90% of aluminum grades
- Easy to machine — 78/100, better than 89% of aluminum grades
Limitations
- Needs corrosion protection — 30/100, worse than 98% of aluminum grades
- Difficult to weld — 20/100, worse than 89% of aluminum grades
2124 properties
Typical room-temperature values; bars are the position among aluminum grades.
Physical3
2124 has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 502°C (936 °F).
Mechanical12
2124 has a yield strength of 440 MPa (63.8 ksi) and a tensile strength of 490 MPa (71.1 ksi) — stronger than 91% of aluminum grades. Elongation at break is 8% and the elastic modulus is 73.1 GPa (10.6 Msi).
Thermal6
2124 is rated for continuous service to 150°C (302 °F). It conducts heat at 152 W/m·K (87.8 BTU/hr·ft·°F), better than 66% of aluminum grades. Thermal expansion is 22.9 µm/m·K (12.7 µin/in·°F).
Electrical3
2124 conducts electricity at 38 % IACS, better than 61% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is poor (30/100), worse than 98% of aluminum grades.
Sustainability4
Producing a kilogram of 2124 takes about 210 MJ of energy and emits 12.5 kg of CO₂ — more than 88% of aluminum grades. Typical recycled content is 5%.
Manufacturability7
2124's machinability is very good (78/100, better than 89% of aluminum grades); weldability poor (20/100); formability poor (25/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. 2124 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 2124
Is 2124 easy to machine?
Excellent chip control in T851; use sharp carbide, high speed and flood coolant — plate is stress-relieved so machined parts stay dimensionally stable.
Can 2124 be welded?
Not recommended for fusion welding (hot cracking, loss of temper); join by riveting, bolting or friction-stir welding with qualified procedures.
Can 2124 be formed, bent or molded?
Form in O or T351 condition only; T851 plate is essentially non-formable and should be machined to shape.
Manufacturability
The process limits FabDigit applies to 2124. Every 2124 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Better78 / 100 |
|---|---|
| ISO material group | N.1 |
| Cutting speed (rough / finish) | 350 / 420 m/min |
| Minimum wall | 0.5 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 8× diameter |
| Best surface (machined / polished) | Ra 0.8 / — |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair25 / 100 |
|---|---|
| Weldability | Poor20 / 100 |
2124 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Sicontrolled low for toughness | ≤ 0.2 | |
| Fecontrolled low for toughness | ≤ 0.3 | |
| Cu | 3.8 – 4.9 | 4.4 |
| Mn | 0.3 – 0.9 | 0.6 |
| Mg | 1.2 – 1.8 | 1.5 |
| Cr | ≤ 0.1 | |
| Zn | ≤ 0.25 | |
| Ti | ≤ 0.15 | |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 2124?
Anodize (chromic/sulfuric per MIL-A-8625) or conversion-coat plus primer is mandatory for corrosion protection; alclad or shot peening improves fatigue/exfoliation life.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Conversion Coating
PVD Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 2124 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- A92124
- Aluminum Association
- AA2124
- EN / DIN / Werkstoff-Nr.
- AW-2124AW 21243.1354
- Also called
- 2124-T851
How much does 2124 cost?
2124 is a premium-cost aluminum ($$$), cheaper than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
2124 — frequently asked
What is 2124 used for?
2124 is typically used for aerospace plate, bulkheads and wing skins. In short: high-purity aerospace plate; improved 2024.
What is the yield strength of 2124?
2124 has a typical yield strength of 440 MPa (63.8 ksi) and a tensile strength of 490 MPa (71.1 ksi) — stronger than 91% of aluminum grades. Strength varies by condition: see the 5 listed tempers.
Is 2124 easy to machine?
Yes — machinability is rated very good (78/100, better than 89% of aluminum grades). Excellent chip control in T851; use sharp carbide, high speed and flood coolant — plate is stress-relieved so machined parts stay dimensionally stable.
Can 2124 be welded?
Not readily — weldability is rated poor (20/100). Not recommended for fusion welding (hot cracking, loss of temper); join by riveting, bolting or friction-stir welding with qualified procedures.
What surface finishes work on 2124?
Anodize (chromic/sulfuric per MIL-A-8625) or conversion-coat plus primer is mandatory for corrosion protection; alclad or shot peening improves fatigue/exfoliation life.
Can 2124 be formed, bent or molded?
Form in O or T351 condition only; T851 plate is essentially non-formable and should be machined to shape.
What is the maximum service temperature of 2124?
2124 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does 2124 cost?
2124 is a premium-cost aluminum ($$$), cheaper than about 58% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in 2124?
Yes — 2124 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- AMS 4101 — Aluminum Alloy Plate 2124-T851 — SAE International (2018)
- EN 573-3 / EN 485-2 wrought aluminium plate — CEN (2019)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- MMPDS-17 (Metallic Materials Properties Development and Standardization) — Battelle/FAA (2022)
- Aerospace plate alloy datasheets (2124-T851) — Constellium / Arconic (2021)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.