O (annealed)
Softest condition for heavy cold heading. Rivets and blanks headed in O are solution treated and aged afterwards.
Aerospace wire · rivets & fasteners
2024 Aerospace Aluminium Rivet Wire
2024 wire is the high-strength aluminium-copper-magnesium wire used to make "DD" solid rivets, pins and special fasteners for aircraft structure. After heat treatment it gives about 280 MPa shear strength, among the highest of the standard aluminium rivet alloys. Metline supplies 2024 rivet and cold-heading wire in coils and straight lengths, in O, T3, T4, T351 and T851, certified to ASTM and AMS specifications, worldwide.
- Alloy
- 2024 (Al-Cu-Mg)
- Tempers
- O, T3, T4, T351, T851
- Diameter
- about 2 – 30 mm
- Standards
- ASTM B316 · ASTM B211 · AMS
Why 2024 wire is used for aircraft rivets
Solid rivets are still the most common permanent fastener in aluminium airframes. Each rivet alloy is identified by a letter code and a head marking: 1100 (A), 2117 (AD), 2017 (D), 2024 (DD), 5056 (B) and 7050 (E). 2024 rivets are the strongest of the traditional group and are used where joints carry high shear loads.
The catch is how 2024 behaves after heat treatment. Freshly solution-treated 2024 is soft enough to drive, but it begins to harden at room temperature within minutes. 2024 and 2017 rivets are therefore known as "icebox rivets": they are solution treated, quenched and then held in a freezer to delay natural ageing, and must be driven within a short working time after removal, typically 10 – 20 minutes. Once driven, they age to full strength over several days. Many modern designs replace them with 7050 "E" rivets or 2117 rivets that can be driven as received, but DD rivets remain on many existing aircraft and repair schemes.
The wire itself must head cleanly. That means tight diameter tolerance, a smooth surface free of seams and laps, consistent chemistry and a uniform grain structure, because any defect opens up as a crack when the head is upset to about 1.5 times the shank diameter.
2024 composition (wt %)
| Element | 2024 (AA / ASTM, EN AW-2024) | 2A12 (GB, close equivalent) | Role |
|---|---|---|---|
| Copper (Cu) | 3.8 – 4.9 | 3.8 – 4.9 | Main strengthening element |
| Magnesium (Mg) | 1.2 – 1.8 | 1.2 – 1.8 | With Cu forms the Al2CuMg (S-phase) precipitates |
| Manganese (Mn) | 0.30 – 0.9 | 0.30 – 0.9 | Grain control, toughness |
| Silicon (Si) | 0.50 max | 0.50 max | Impurity |
| Iron (Fe) | 0.50 max | 0.50 max | Impurity; low Fe improves toughness |
| Chromium (Cr) | 0.10 max | — | Impurity |
| Nickel (Ni) | — | 0.10 max | Impurity |
| Zinc (Zn) | 0.25 max | 0.30 max | Impurity |
| Titanium (Ti) | 0.15 max | 0.15 max | Grain refiner |
| Others, each / total | 0.05 / 0.15 | 0.05 / 0.10 | |
| Aluminium (Al) | Remainder | Remainder | About 90.7 – 94.7 % |
Some listings give silicon for 2024 as 0.5 – 0.9 %. The registered limit is 0.50 % maximum; silicon is an impurity in this alloy.
Mechanical and physical properties
For rivets the key value is shear strength. 2024-T4 material has a typical shear strength of about 283 MPa (41 ksi); design allowables for driven rivets are taken from MMPDS or the airframe maker's data, not from wire tensile values.
| Temper | Tensile strength | Yield strength (0.2 %) | Elongation | Brinell hardness | Shear strength |
|---|---|---|---|---|---|
| O | 186 MPa / 27 ksi | 76 MPa / 11 ksi | 20 % | 47 HB | 125 MPa |
| T3 | 483 MPa / 70 ksi | 345 MPa / 50 ksi | 18 % | 120 HB | 283 MPa |
| T4, T351 | 469 MPa / 68 ksi | 324 MPa / 47 ksi | 19 – 20 % | 120 HB | 283 MPa |
| T6 | 476 MPa / 69 ksi | 393 MPa / 57 ksi | 10 % | 125 HB | 283 MPa |
| T81, T851 | 483 MPa / 70 ksi | 448 MPa / 65 ksi | 6 % | 128 HB | 296 MPa |
Physical properties of 2024
- Density
- 2.78 g/cm³ (0.100 lb/in³)
- Modulus of elasticity
- about 73 GPa (10.6 Msi)
- Poisson's ratio
- 0.33
- Fatigue strength (5×10⁸ cycles, T3/T4)
- about 138 MPa
- Melting range
- about 502 – 638 °C
- Thermal conductivity
- about 121 W/m·K (T3/T4); about 151 W/m·K (T8)
- Electrical conductivity
- about 30 % IACS (T3/T4); about 38 % IACS (T8)
- Coefficient of thermal expansion
- about 23.2 µm/m·°C (20 – 100 °C)
Wire tempers and when to use them
T4
Solution treated and naturally aged: the standard condition for 2024 rivet wire and for rivets supplied heat-treated.
T3
Solution treated, cold worked (drawn) and naturally aged; tighter diameter control and slightly higher strength for screw-machine and pin stock.
T351
Stretched to relieve stress; for straight lengths machined into pins and bushings.
T851
Stretched and artificially aged for higher yield strength and better stress-corrosion resistance; used for pins and machined parts that run warm.
Driven rivets
Icebox rivets driven after quenching age at room temperature; the installed condition is commonly referred to as T31.
Specifications and equivalents
Wire and rivet specifications
- ASTM B316 / B316M
- Aluminium and aluminium-alloy rivet and cold-heading wire and rods
- ASTM B211
- Rolled or cold-finished bar, rod and wire
- AMS-QQ-A-430
- Aluminium alloy rod and wire for rivets and cold heading (former QQ-A-430)
- AMS 4120 / AMS-QQ-A-225/6
- 2024 bar, rod and wire
- Rivet standards
- NAS and MS rivet standards (for example MS20470 and MS20426) define DD rivets made from this wire
- EN 573-3
- EN AW-2024 composition
| System | Designation |
|---|---|
| Aluminum Association / UNS | 2024 / A92024 |
| European (EN) | EN AW-2024 / AlCu4Mg1 |
| German Werkstoff / DIN | 3.1355 / AlCuMg2 |
| ISO | AlCu4Mg1 |
| France (old NF) | AU4G1 |
| Japan (JIS) | A2024 |
| China (GB) | 2A12 (close equivalent) |
Supply range
Supply range
- Diameter
- about 2 – 30 mm (0.08 – 1.18 in), including standard rivet sizes from 3/32 in upward
- Tolerance
- To ASTM B316 or ASTM B211; close-tolerance heading wire on request
- Form
- Coils, spools or straightened lengths of 1 – 6 m
- Shapes
- Round as standard; square, hexagon and flat on request
- Surface
- Bright drawn, lubricated for heading or dry
Testing and inspection
- Chemistry per melt and tensile tests per lot
- Heading (upset) test and shear test of heat-treated samples when specified
- Diameter and ovality checked along the coil
- Surface inspection for seams, laps and scratches
- Conductivity check of heat-treated samples
- EN 10204 3.1 certificate with full traceability
Applications
- DD solid rivets for fuselage and wing joints with high shear loads
- Repair rivets for aircraft built with 2024 rivets
- Pins, bushings and spacers machined from T3 or T351 stock
- Special fasteners and cold-headed parts
- Defence and space hardware requiring high-strength aluminium fasteners
2024 compared with other rivet alloys
| Rivet alloy (code) | Typical shear strength | Driven condition | Notes |
|---|---|---|---|
| 1100 (A) | ~75 MPa | As received | Non-structural |
| 2117 (AD) | ~195 MPa | As received (T4) | Most common structural rivet |
| 2017 (D) | ~260 MPa | Icebox or as received | Higher strength |
| 2024 (DD) | ~283 MPa | Icebox after quench | Highest of the classic 2xxx rivets |
| 5056 (B) | ~180 MPa | As received | Used with magnesium structure |
| 7050 (E) | ~300 MPa | As received (T73) | Modern replacement for DD |
Approximate typical values for comparison only; use MMPDS or OEM allowables for design.
How to order
- SpecifyAlloy and temper, diameter and tolerance, coil or length format, and quantity.
- Name the standardASTM B316, ASTM B211, AMS-QQ-A-430 or your fastener specification.
- QuoteWe confirm availability, tolerance, test scope, certification and delivery terms (EXW, FOB, CIF or DAP) for your port or site.
- Process and inspectWire is coiled or straightened, labelled per coil and checked for size and surface.
- Document and shipEach lot ships with an EN 10204 3.1 mill test certificate traceable to the heat and lot, plus a packing list. Material is packed in seaworthy wooden cases with moisture protection; third-party inspection can be arranged on request.
References and standards
- ASTM B316/B316M – Aluminum and Aluminum-Alloy Rivet and Cold-Heading Wire and Rods
- ASTM B211 – Aluminum and Aluminum-Alloy Rolled or Cold-Finished Bar, Rod and Wire
- FAA-H-8083-31 Aviation Maintenance Technician Handbook – Airframe, Vol. 1, Ch. 4: Aircraft Metal Structural Repair
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits
2024 aluminium (aluminum) rivet wire: FAQ
Why are 2024 rivets called icebox rivets?
After solution treatment they harden quickly at room temperature. Keeping them frozen delays ageing so they can still be driven; once removed they must be used within a short time, typically 10 – 20 minutes.
What is the head marking of a 2024 rivet?
DD rivets carry two raised dashes on the head.
Which temper should I order for rivet manufacture?
Usually T4 or O, depending on whether the rivets are headed before or after heat treatment. Agree the temper with your heading process.
Is 2024 wire still used for new aircraft?
Less than before; many designs use 7050 E rivets or 2117 AD rivets instead. 2024 remains in use for existing designs, repairs and special fasteners.
What is the shear strength of 2024 rivets?
Typical shear strength of 2024-T4 material is about 283 MPa (41 ksi). Use published allowables for design.
Need 2024 rivet or heading wire?
Send diameter, temper, format and quantity and we will confirm availability and a delivered price.
