Cold heading
Annealed 5056 heads well but work-hardens quickly; keep heading speeds and die clearances matched to the wire size.
Aerospace · rivet wire
5056 Aerospace Aluminium Wire
5056 is a 5 % magnesium aluminium alloy drawn into wire for aircraft rivets, especially rivets used to join magnesium alloy parts, and for other cold-headed fasteners, mesh and cable armour. It is supplied annealed (5056-O) to AMS 4182 and to rivet-wire specifications such as QQ-A-430. Metline supplies 5056 wire in coils or straight lengths with mill certificates, worldwide.
- Alloy
- 5056 (Al-5Mg-0.12Mn-0.12Cr)
- Temper
- O (also H32, H18, H38)
- Diameter
- Typically 1.6 – 10 mm
- Standards
- AMS 4182 · QQ-A-430
What 5056 wire is used for
5056 has the highest magnesium content of the common wrought 5xxx alloys, about 5 %. That gives it high strength from cold work alone, good corrosion resistance and, importantly for aircraft builders, good galvanic compatibility with magnesium alloys.
The main aerospace use is rivet wire. Rivets headed from 5056 wire carry the code letter B in AN and MS rivet standards and are identified by a raised cross on the head. They are specified mainly for joining magnesium alloy structure, where aluminium-copper rivets such as 2117 or 2017 would set up a strong galvanic couple and corrode the surrounding magnesium. 5056 rivets are driven as received, without the solution heat treatment and ice-box storage that 2017 and 2024 rivets need.
Beyond rivets, 5056 wire is cold headed into pins and small fasteners, woven into screens, used as armour and sheathing on cables, and drawn into the foil used for high-strength honeycomb core.
5056 chemical composition (wt %)
The limits below are the registered values that AMS 4182 and QQ-A-430 follow. Note that 5056 is an aluminium-magnesium alloy with almost no copper. Some published tables for "5056 wire" show 4.5 – 5.6 % copper and less than 2 % magnesium; that is a 2xxx-series composition and is wrong for 5056.
| Element | Minimum | Maximum | Role in the alloy |
|---|---|---|---|
| Silicon (Si) | — | 0.30 | Impurity |
| Iron (Fe) | — | 0.40 | Impurity |
| Copper (Cu) | — | 0.10 | Kept low for corrosion resistance and magnesium compatibility |
| Manganese (Mn) | 0.05 | 0.20 | Grain control and strength |
| Magnesium (Mg) | 4.5 | 5.6 | Main strengthening element |
| Chromium (Cr) | 0.05 | 0.20 | Grain control, stress-corrosion resistance |
| Zinc (Zn) | — | 0.10 | Impurity |
| Others, each / total | — | 0.05 / 0.15 | |
| Aluminium (Al) | Remainder | About 93.0 – 95.4 % |
Mechanical and physical properties
Typical values for 5056 wire by temper are shown below. Rivet-wire specifications set their own tensile limits and require head-upsetting and shear tests; the certificate supplied with the lot reports the results.
| Temper | Typical tensile | Typical yield | Typical elongation | Typical shear strength |
|---|---|---|---|---|
| O (annealed) | 290 MPa / 42 ksi | 152 MPa / 22 ksi | 35 % | 179 MPa / 26 ksi |
| H38 | 414 MPa / 60 ksi | 345 MPa / 50 ksi | 15 % | 221 MPa / 32 ksi |
| H18 | 434 MPa / 63 ksi | 407 MPa / 59 ksi | 10 % | 234 MPa / 34 ksi |
Driven 5056 rivets gain strength from the cold work of heading; design shear values for B rivets are taken from MMPDS or the airframe manufacturer's data, not from wire properties.
Physical properties
- Density
- 2.64 g/cm³ (0.095 lb/in³)
- Modulus of elasticity
- 71 GPa (10,300 ksi)
- Electrical conductivity
- About 29 % IACS
- Thermal conductivity
- About 112 – 117 W/m·K
- Melting range
- 568 – 638 °C
Rivet wire diameters and uses
| Rivet size | Nominal diameter | Typical use |
|---|---|---|
| -3 (3/32 in) | 2.38 mm | Thin sheet, fairings, small brackets |
| -4 (1/8 in) | 3.18 mm | General riveting of skins and stiffeners |
| -5 (5/32 in) | 3.97 mm | Heavier skins and frames |
| -6 (3/16 in) | 4.76 mm | Thick joints, spar and frame attachments |
| -8 (1/4 in) | 6.35 mm | Heavy joints and fittings |
Rivet wire is drawn slightly under the nominal rivet diameter so it feeds through heading machines; tell us the heading process and the diameter tolerance you need. Wire is supplied in coils for automatic heading or in straight lengths. Other diameters from about 1.6 mm to 10 mm are produced to order.
Specifications
| Specification | Scope |
|---|---|
| SAE AMS 4182 | 5056-O annealed wire |
| QQ-A-430 | Aluminium alloy rod and wire for rivets and cold heading, including 5056 |
| ASTM B316 | Aluminium and aluminium-alloy rivet and cold-heading wire and rod |
| L58 (British legacy) | Rivet stock in 5056A, cited on older British drawings |
| UNS / EN | A95056; European variant EN AW-5056A (AlMg5) |
Heading, corrosion and temperature limits
Magnesium joints
Use 5056 rivets with primed or sealed faying surfaces; never 2xxx rivets in magnesium structure.
Temperature
With more than 3 % magnesium, 5056 can become sensitised to intergranular and stress corrosion after long exposure above about 65 °C. Keep it out of hot zones.
5056 wire should not be confused with ER5356 welding wire. The two compositions are similar, but welding filler is made to AWS A5.10 with titanium additions and cleanliness requirements for welding, while 5056 rivet wire is made for heading and shear performance.
How to order
- SpecifyAlloy and temper, diameter and tolerance, coil or straight lengths, quantity and the governing specification with its revision (AMS 4182, QQ-A-430 or ASTM B316).
- ConfirmWe confirm the specification can be met, the tolerance class, any extra tests and the delivery terms (EXW, FOB, CIF or DAP).
- InspectMaterial is checked for dimensions, straightness and surface condition; tests named on the order are carried out or arranged with a third party.
- DocumentEach lot ships with a mill test certificate to EN 10204 3.1 showing chemistry and mechanical results, traceable to the cast or lot number.
- Pack and shipExport packing in sealed, moisture-protected wooden cases or on pallets, shipped by sea or air to your port or door.
References and standards
- SAE AMS 4182 – Aluminum Alloy Wire, 5.0Mg - 0.12Mn - 0.12Cr (5056-O), Annealed
- QQ-A-430 – Aluminum Alloy Rod and Wire; for Rivets and Cold Heading
- ASTM B316 – Aluminum and Aluminum-Alloy Rivet and Cold-Heading Wire and Rods
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits (Teal Sheets)
- ASM Handbook, Vol. 2 – Properties and Selection: Nonferrous Alloys and Special-Purpose Materials
5056 aerospace aluminium (aluminum) wire: FAQs
Why are 5056 rivets used with magnesium?
5056 contains almost no copper and sits close to magnesium in the galvanic series, so it causes far less corrosion in magnesium structure than copper-bearing 2xxx rivets.
Does 5056 rivet wire need heat treatment before driving?
No. 5056 is not heat treatable; rivets are driven as received, unlike 2017 and 2024 rivets that must be solution treated and kept cold.
How are 5056 rivets identified?
In AN and MS rivet standards the material code is B, and the head carries a raised cross.
What is the chemical composition of 5056?
Magnesium 4.5 – 5.6 %, manganese 0.05 – 0.20 %, chromium 0.05 – 0.20 %, copper 0.10 % max, balance aluminium.
Can 5056 be used at high temperature?
Avoid long service above about 65 °C, where alloys with more than 3 % magnesium can become sensitised to intergranular corrosion.
Need 5056 rivet or heading wire?
Send diameter, temper, specification and quantity. We will reply with availability, certification and a delivered price.
