T3 / T3510 / T3511
Solution heat-treated, stretched and naturally aged. T3510 is stretched with no further straightening; T3511 allows minor straightening. The standard choice for most parts.
High-strength extrusions for demanding parts
2024 and 2024A T3 Aluminium Extrusions for Automotive
2024 is a high-strength aluminium-copper-magnesium alloy, best known from aircraft structures, that is also extruded as bar, tube and profiles for highly loaded automotive and motorsport parts. In the stretched T3511 temper it combines high strength with excellent fatigue resistance. Metline supplies 2024 and 2024A extrusions to ASTM B221, EN 755 and AMS specifications worldwide.
- Alloy
- 2024 / 2024A (Al-Cu-Mg)
- Tempers
- T3, T3510, T3511, T4, T8511
- Forms
- Bar, tube, angle, tee, channel, custom
- Standards
- ASTM B221 · EN 755 · AMS-QQ-A-200/3
What are 2024 extrusions used for in vehicles?
2024 contains about 4.4 % copper and 1.5 % magnesium. After solution treatment, quenching, stretching and natural ageing (T3511), extrusions reach tensile strengths of roughly 400 – 500 MPa depending on section thickness, with fatigue performance that has kept the alloy in aircraft wings and fuselages for decades.
In automotive work 2024 is a specialist material. It appears where a machined or extruded part is highly loaded and weight is critical: racing suspension links and uprights machined from bar, high-performance driveline and steering components, fasteners, and precision fittings in hydraulic systems. Mass-produced body and chassis structures use 6xxx extrusions instead, because 2024 cannot be fusion welded and needs corrosion protection.
2024A is a registered variant of 2024 with tighter limits on iron, silicon and some alloying elements, developed to improve toughness and reduce residual stress. Unless your drawing specifies 2024A, standard 2024 is the more widely available choice.
2024 chemical composition (wt %)
| Element | Minimum | Maximum | Role |
|---|---|---|---|
| Silicon (Si) | — | 0.50 | Impurity |
| Iron (Fe) | — | 0.50 | Impurity; lowered in 2024A for toughness |
| Copper (Cu) | 3.8 | 4.9 | Main strengthening element |
| Manganese (Mn) | 0.30 | 0.9 | Strength and grain control |
| Magnesium (Mg) | 1.2 | 1.8 | Strengthening with copper (S-phase) |
| Chromium (Cr) | — | 0.10 | |
| Zinc (Zn) | — | 0.25 | Impurity |
| Titanium (Ti) | — | 0.15 | Grain refiner |
| Others, each / total | — | 0.05 / 0.15 | |
| Aluminium (Al) | Remainder |
Registered Aluminum Association limits for 2024 (EN AW-2024, AlCu4Mg1). 2024A narrows the ranges and lowers impurity maximums; we supply against the exact limits on your drawing.
Mechanical properties of 2024 extrusions
For extrusions, specified minimum strength in T3-type tempers increases with section thickness. The values below summarise ASTM B221 for 2024-T3 / T3510 / T3511 in the longitudinal direction; transverse values are lower.
| Section thickness | Tensile strength (min.) | Yield strength (min.) | Elongation (min.) |
|---|---|---|---|
| up to 6.3 mm | 395 MPa / 57 ksi | 290 MPa / 42 ksi | 12 % |
| 6.3 – 19 mm | 415 MPa / 60 ksi | 305 MPa / 44 ksi | 12 % |
| 19 – 38 mm | 450 MPa / 65 ksi | 315 MPa / 46 ksi | 10 % |
| over 38 mm | 485 MPa / 70 ksi | 360 MPa / 52 ksi | 10 % |
Summary of ASTM B221 minimums; the current edition and the certificate govern. AMS specifications may set different values and test directions.
Physical properties (T3)
- Density
- 2.78 g/cm³
- Modulus of elasticity
- 73 GPa
- Shear strength (typical)
- about 280 – 285 MPa
- Fatigue strength (typical, 5×10⁸ cycles)
- about 138 MPa
- Thermal conductivity
- about 120 W/m·K
- Electrical conductivity
- about 30 % IACS
- Melting range
- about 502 – 638 °C
2024 extrusion tempers
T4
Solution heat-treated and naturally aged without controlled stretching; used for some bar and rivet stock.
T8510 / T8511
Stretched then artificially aged. Higher yield strength and much better resistance to stress-corrosion cracking, with slightly lower elongation; preferred for parts exposed to sustained stress or moderate heat.
O
Annealed for forming, followed by heat treatment by the user.
Standards and equivalents
| System | Designation / standard |
|---|---|
| ASTM | B221 (extrusions), B241 (seamless tube and pipe), B211 (cold-finished bar) |
| SAE AMS | AMS-QQ-A-200/3 (2024 extrusions); AMS 4152 and related AMS extrusion specifications for T3-family tempers |
| European (EN) | EN AW-2024 / AlCu4Mg1 and EN AW-2024A; EN 755-2, EN 573-3 |
| UNS / Werkstoff | A92024 / 3.1355 |
| Japan (JIS) | A2024; JIS H4100 (extruded shapes) |
2024 extrusion supply range
Typical supply range
- Round bar
- About 10 – 250 mm diameter
- Square, hex and flat bar
- Common metric and imperial sizes
- Tube
- Extruded and drawn round, square and rectangular tube
- Profiles
- Angles, tees, channels, Z and H sections and custom shapes to drawing
- Lengths
- Mill lengths up to about 6 m, or cut to length
- Inspection
- Ultrasonic inspection of bar to AMS-STD-2154 on request
Machining, joining and corrosion protection
Machining
Machines well in T3 / T3511 with good chip control; T8511 machines even more cleanly. Stretched tempers keep distortion low.
Welding
Not suitable for arc welding: hot cracking and large strength loss. Friction-stir welding is possible in specialised applications. Fasten mechanically or bond.
Corrosion
Lower resistance than 6xxx alloys, with susceptibility to intergranular corrosion and stress-corrosion cracking in T3. Anodise (sulphuric or chromic-free processes), prime and paint exposed parts.
Temperature
T3 strength declines with long exposure above about 120 °C; T8 tempers are more stable.
Galvanic contact
Isolate from steel and carbon fibre with coatings, sealants and washers.
Surface finish
Hard anodising gives a wear-resistant surface for sliding parts.
Automotive and motorsport applications
- Suspension components: machined uprights, rocker arms, links and brackets in racing and performance cars
- Driveline and steering: splined couplings, spacers and steering-column parts machined from bar
- Fasteners: high-strength aluminium bolts and rivets
- Hydraulic fittings: couplings and housings for brake-system and clutch hydraulics, away from road spray
- Motorsport structures: roll-hoop fittings, wing mounts and pick-up points
Pistons, connecting rods and engine blocks are usually cast or forged from other alloys (such as 4032, 2618 and cast Al-Si), and wheels and brake discs are not made from 2024. These claims in some product literature are not correct.
2024 compared with 2017, 6082 and 7075
| Property | 2024-T3511 | 2017-T4 | 6082-T6 | 7075-T6511 |
|---|---|---|---|---|
| Typical tensile strength | ~470 – 485 MPa | ~427 MPa | ~310 MPa | ~570 MPa |
| Fatigue resistance | Excellent | Good | Good | Good |
| Weldability | Poor | Poor | Good | Poor |
| Corrosion resistance | Fair | Fair | Good | Fair |
| Relative cost | High | Medium | Low | High |
Choose 7075 for maximum static strength, 2024 for fatigue-critical parts, and 6082 or 6061 when the part must be welded or is produced in high volume.
How to order 2024 extrusions
- SpecifyAlloy (2024 or 2024A), temper (e.g. T3511), section or bar size, length, quantity and any ultrasonic class.
- Confirm the standardASTM B221, EN 755-2 or the AMS specification on your drawing.
- QuoteWe confirm availability, tolerances, certification and delivery terms (EXW, FOB, CIF or DAP) for your plant or port.
- Process and inspectMaterial is cut, inspected for dimensions and surface and, where ordered, ultrasonically tested.
- Document and shipEach lot ships with an EN 10204 3.1 mill test certificate, heat or lot traceability and a packing list, in seaworthy export packing. Third-party inspection can be arranged on request.
References and standards
- ASTM B221 – Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes
- SAE AMS-QQ-A-200/3 – Aluminum Alloy 2024, Bar, Rod, Shapes, Tube and Wire, Extruded
- EN 755-2 – Extruded rod/bar, tube 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)
2024 aluminium (aluminum) extrusions for automotive: frequently asked questions
What is the difference between 2024 and 2024A?
2024A is a registered variant with narrower composition ranges and lower impurities, aimed at better toughness and lower residual stress. Standard 2024 is more widely stocked; order 2024A when the drawing requires it.
What does T3511 mean?
Solution heat-treated, stress-relieved by stretching, with minor straightening allowed, then naturally aged. It is the most common temper for 2024 extrusions.
Can 2024 extrusions be welded?
Not by conventional arc welding. The alloy cracks and loses much of its strength. Use bolts, rivets or adhesive bonding.
Is 2024 used for car wheels or brake discs?
No. Wheels are cast or forged in alloys such as A356, 6061 and 6082, and brake discs are cast iron or ceramic composites. 2024 is used for machined, highly loaded fittings and fasteners.
How strong is 2024-T3511?
ASTM B221 minimum tensile strength ranges from about 395 MPa for thin sections to 485 MPa for sections over 38 mm thick.
Do you supply 2024 extrusions internationally?
Yes. Metline ships 2024 bar, tube and profiles worldwide with EN 10204 3.1 certificates and export packing.
Need 2024 extrusions?
Send the size, temper, specification and quantity. Our team will reply with availability and a delivered quotation.
