Anodising
Clear, coloured and hard anodising give an even appearance; chromic or boric-sulphuric anodising where aerospace specifications require it.
Aerospace · Architectural-grade extrusions
6063 Aerospace Aluminium Profiles & Extrusions
6063 is the easiest aluminium alloy to extrude into thin-walled, intricate and hollow profiles with a smooth, anodise-ready surface. In aerospace it is used for cabin interior systems, trim, lighting and seat components, cable management and ground equipment rather than primary structure. Metline supplies standard and custom 6063 profiles in T4, T5, T6 and T66, certified to AMS 4156, ASTM B221 or EN 755, worldwide.
- Alloy
- 6063 (Al-Mg-Si)
- Tempers
- O, T4, T5, T6, T66
- Section size
- Up to about 850 mm wide
- Standards
- AMS 4156 · ASTM B221 · EN 755
Why 6063 is chosen for aircraft profiles
Low silicon, magnesium and iron give 6063 a soft, fluid billet at extrusion temperature. Profiles can be pushed fast through complex dies, including multi-void hollows and thin fins, and the alloy can be quenched with air at the press exit and still reach good T5 or T6 properties.
Aircraft cabins contain long runs of extruded section: sidewall and ceiling trim, light housings, passenger service unit rails, seat-track covers, partition frames, galley and lavatory trim, overhead-bin edging and cable raceways. These parts need tight shape control, a flawless decorative finish and light weight, but carry only modest loads. 6063 meets those needs at the lowest cost of any aerospace-acceptable extrusion alloy, and SAE AMS 4156 covers it for exactly this purpose: parts where surface finish and intricate or hollow shapes count.
For structural sections, such as floor beams or seat tracks themselves, designers move to 6061, 2024 or 7075 extrusions. A useful rule: if the profile appears on a stress analysis, check whether 6063 is strong enough; if it appears mainly on a styling drawing, 6063 is usually right.
6063 chemical composition (wt %)
Registered Aluminum Association limits, matching ASTM B221, AMS 4156 and EN 573-3 (EN AW-6063). Nickel is not a specified element in 6063; it falls under "others".
| Element | Minimum | Maximum | Role in the alloy |
|---|---|---|---|
| Silicon (Si) | 0.20 | 0.60 | Forms Mg2Si with magnesium |
| Iron (Fe) | — | 0.35 | Kept low for bright finish and extrudability |
| Copper (Cu) | — | 0.10 | Low, protects corrosion resistance |
| Manganese (Mn) | — | 0.10 | Residual |
| Magnesium (Mg) | 0.45 | 0.90 | Main strengthening element with Si |
| Chromium (Cr) | — | 0.10 | Residual |
| Zinc (Zn) | — | 0.10 | Impurity |
| Titanium (Ti) | — | 0.10 | Grain refiner |
| Others, each / total | — | 0.05 / 0.15 | |
| Aluminium (Al) | Remainder | About 97.5 – 99.4 % |
Mechanical properties of 6063 extrusions by temper
Minimums below follow EN 755-2 for profiles up to about 25 mm wall, with ASTM B221 values in brackets where they differ. Designs must use the minimums on the certificate; typical values are 10 – 20 % higher.
| Temper | Tensile strength (min) | Yield strength 0.2 % (min) | Elongation A (min) |
|---|---|---|---|
| O / H111 | ≤ 130 MPa (max) | — | 18 % |
| T4 | 130 MPa | 65 MPa (ASTM 69 MPa) | 14 % |
| T5 | 175 MPa (ASTM 152 MPa) | 130 MPa (ASTM 110 MPa) | 6 – 8 % |
| T6 | 215 MPa (ASTM 207 MPa) | 170 MPa (ASTM 172 MPa) | 8 – 10 % |
| T66 | 245 MPa | 200 MPa | 8 – 10 % |
Some data sheets list the T6 yield of 6063 as 70 MPa; that is an error, the correct minimum is about 170 MPa. They also offer "T651", which is a plate temper. Stress-relieved extrusions are designated T6510 (stretched, not straightened) or T6511 (stretched with minor straightening).
Physical properties (T6)
- Density
- 2.70 g/cm³
- Modulus of elasticity
- 68.9 GPa
- Thermal conductivity
- about 200 W/m·K
- Electrical conductivity
- about 53 % IACS
- Coefficient of thermal expansion
- 23.4 µm/m·°C
Designing a 6063 profile: practical limits
| Feature | Typical guidance for 6063 | Why it matters |
|---|---|---|
| Circumscribing circle | Up to about 600 mm on large presses; most profiles under 250 mm | Sets press size and die cost |
| Minimum wall (small open profiles) | About 0.8 – 1.0 mm | Thinner walls risk tearing and shape loss |
| Minimum wall (hollows) | About 1.0 – 1.5 mm | Bridge or porthole dies need metal to weld inside the die |
| Wall thickness ratio | Keep adjacent walls within about 3:1 | Uneven walls cool unevenly and distort |
| Tongue ratio (slot depth to width) | Up to about 3:1 for standard dies | Deep narrow slots break die tongues |
| Corner radii | 0.5 mm minimum where possible | Improves flow and anodised appearance |
Overall envelopes depend on the extruder: very small open sections from about 4 × 3 mm, open profiles up to about 850 mm wide, closed profiles from about 6 mm across, and weights from roughly 0.03 kg/m to over 100 kg/m. Standard length is 6 m, with longer lengths by agreement. Send the drawing early; small changes to radii or wall ratios often reduce die cost and improve tolerance.
Standards, tolerances and designations
| System | Designation / standard | Scope |
|---|---|---|
| SAE AMS | AMS 4156 | 6063-T6 extrusions (bar, rod, profiles, tube) |
| ASTM / ASME | ASTM B221 / SB-221 | Extruded profiles; tolerances per ANSI H35.2 |
| European | EN 755-2; EN 755-9 (profile tolerances); EN 12020-2 (precision profiles) | Properties and tolerances |
| US Federal (legacy) | QQ-A-200/9 | Cancelled; replaced by ASTM B221 / AMS 4156 |
| British (legacy) | H9 (BS 1474) | Superseded by EN 755 |
| UNS / Werkstoff | A96063 / 3.3206 | — |
| Japan | A6063S | JIS H4100 (shapes) |
EN 12020-2 gives tighter tolerances than EN 755-9 and is often used for interior parts that must fit snugly with mating panels. State on the order which tolerance standard applies.
Machining, joining and finishing 6063 profiles
Paint and powder
Chromate-free conversion coatings followed by primer, paint or powder coat for interior colour schemes.
Machining
CNC punching, drilling and milling are routine; use sharp tools to avoid burrs on thin walls.
Bending
Stretch-bend or roll-bend in T4, then age to T6. T5 and T6 sections bend only to generous radii.
Joining
TIG and MIG weld with ER4043 or ER5356; mechanical fastening and adhesive bonding are common in cabins.
Protection
Interleaving paper or film prevents scuffing of decorative faces during shipping.
Typical aerospace uses of 6063 profiles
- Cabin interior: sidewall and ceiling trim, overhead-bin edging, partition and monument frames
- Lighting: LED wash-light housings and diffuser channels
- Seating: trim, armrest and shroud extrusions on non-structural seat parts
- Cable management: raceways, cable trays and clip rails
- Avionics: card guides, rack rails and finned heat sinks
- Ground support equipment: handrails, platform edging, stairs and covers
6063 profiles compared with 6061, 6005A and 6082
| Property | 6063-T6 | 6005A-T6 | 6061-T6 | 6082-T6 |
|---|---|---|---|---|
| Typical tensile strength | 241 MPa | 285 MPa | 310 MPa | 310 – 340 MPa |
| Extrudability | Excellent | Very good | Fair–good | Fair–good |
| Thin-wall hollow profiles | Excellent | Good | Fair | Fair |
| Decorative anodising | Excellent | Good | Good | Fair–good |
| Typical aerospace role | Interiors, trim | GSE frames | Secondary structure | GSE, European structure |
How to order 6063 aerospace profiles
- SpecifyAlloy and temper, profile drawing or die number, length, finish, quantity and the governing specification with its revision (AMS 4156, ASTM B221 or EN 755-2 with EN 755-9 / EN 12020-2 tolerances).
- 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 4156 – Aluminum Alloy Extrusions, 6063-T6
- ASTM B221 – Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles and Tubes
- EN 755-2 – Aluminium and aluminium alloys: extruded rod/bar, tube and profiles, mechanical properties
- EN 12020-2 – Extruded precision profiles in alloys EN AW-6060 and EN AW-6063: tolerances
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits (Teal Sheets)
- The Aluminum Association – Aluminum Extrusion Manual / Aluminum Standards and Data
6063 aerospace aluminium (aluminum) profiles: FAQs
Is 6063 approved for aerospace use?
Yes, for suitable parts. SAE AMS 4156 covers 6063-T6 extrusions. It is used for interiors, trim and non-structural parts; structural sections use stronger alloys.
What is the yield strength of 6063-T6 extrusions?
The minimum is about 170 MPa (ASTM B221: 172 MPa / 25 ksi), and typical values are around 214 MPa. Figures of 70 MPa seen on some data sheets are wrong.
Can 6063 profiles be supplied in T651?
T651 is a plate temper. For stress-relieved extrusions the correct tempers are T6510 or T6511. Most 6063 profiles are supplied in T5 or T6.
What is the thinnest wall possible in a 6063 profile?
Around 0.8 – 1.0 mm for small open shapes and 1.0 – 1.5 mm for hollows, depending on profile size and the extruder's press.
What is the difference between T5 and T6 for 6063?
T5 is cooled at the press and aged; T6 is fully solution treated and aged and is stronger (215 MPa against 175 MPa minimum tensile under EN 755-2).
Do you supply custom 6063 profiles with a new die?
Yes. Metline arranges custom dies from your drawing and supplies profiles cut, finished and certified to EN 10204 3.1, shipped worldwide.
Need 6063 profiles for a cabin or GSE programme?
Send the drawing, temper, finish, length and quantities. We will reply with die, tolerance, certification and delivered cost.
