T6
Solution heat-treated and artificially aged. Standard temper for 6xxx and 7xxx bar where residual stress is not critical.
Long products
Aluminium Round Bar
Aluminium round bar (round rod, or aluminum rod in the US) is a solid cylindrical section made by extrusion or by extrusion followed by cold drawing. It is the main stock for turned parts, shafts, pins, fittings and machined components. Metline supplies round bar in every common grade, from free-machining 2011 to high-strength 7075, cut to length and certified to ASTM, AMS and EN standards, to customers worldwide.
- Diameter
- about 3 – 500 mm
- Routes
- Extruded, cold drawn, forged
- Main grades
- 6061, 6082, 7075, 2011
- Standards
- ASTM B211 · B221 · EN 754 · EN 755
What is aluminium round bar?
Round bar is the simplest long product in aluminium: a solid circle of constant diameter supplied in straight lengths, typically 3 to 6 metres. It is the default feedstock for CNC lathes and bar-fed turning centres, and is also used directly as shafts, rollers, pins, spacers and electrical conductors.
Two production routes dominate. Extruded bar is pushed hot through a round die and then heat-treated and stretched; it covers the widest diameter range and is the economical choice when the part will be machined all over. Cold-finished (drawn) bar is extruded slightly oversize and then drawn through a die at room temperature, which gives a tighter diameter tolerance, better roundness, a brighter surface and, in some tempers, higher strength. Very large diameters, above roughly 300 mm, are often made as forged or cast-and-homogenised bar.
Buyers sometimes treat a diameter as the whole specification. It is not: an extruded 6082-T6 bar and a drawn 6082-T6 bar of the same nominal size differ in tolerance, straightness and surface, and a 2011-T3 free-machining bar behaves completely differently on a lathe from a 6061-T6 bar. The grade, temper, production route and standard all belong on the order.
Round bar grades and when to use them
| Grade | Type | Key strengths | Typical round bar uses |
|---|---|---|---|
| 6061 | Al-Mg-Si-Cu, heat-treatable | All-round strength, weldability, anodising | Machined parts, fittings, shafts, fixtures |
| 6082 | Al-Si-Mg-Mn, heat-treatable | Slightly higher strength than 6061 in large sizes; European standard grade | Structural and machined parts, hydraulic components |
| 6063 | Al-Mg-Si, heat-treatable | Excellent surface and anodising, moderate strength | Decorative rods, handles, furniture |
| 2011 | Al-Cu-Bi-Pb, free-machining | Small broken chips, high speed turning | Screw-machine parts, fasteners, fittings, inserts |
| 2014 / 2017 / 2024 | Al-Cu, heat-treatable | High strength and fatigue resistance | Aerospace fittings, gears, high-load pins, bolts |
| 7075 | Al-Zn-Mg-Cu, heat-treatable | Highest common strength | Aerospace parts, moulds, sports equipment, high-stress shafts |
| 5083 / 5052 | Al-Mg, non-heat-treatable | Seawater resistance, weldability | Marine fittings, cryogenic components |
| 1100 / 1050 | Commercial purity | Conductivity, formability | Electrical rod, rivet stock, spun parts |
Lead-free free-machining alternatives to 2011, such as 6026 and 6262-type grades, are increasingly specified to comply with environmental limits on lead in parts. Ask if your customer requires RoHS- or ELV-compliant bar.
Typical mechanical properties of round bar
Values below are typical room-temperature properties from Aluminum Association and ASM data for rod and bar. Specified minimums in ASTM B211, B221 and EN 754-2 / EN 755-2 are lower and vary with diameter; design to the minimums shown on your mill certificate.
| Grade and temper | Tensile strength | Yield strength (0.2 %) | Elongation | Brinell hardness |
|---|---|---|---|---|
| 6063-T6 | 241 MPa | 214 MPa | 12 % | 73 HB |
| 6061-T6 / T651 | 310 MPa | 276 MPa | 12 – 17 % | 95 HB |
| 6082-T6 (EN 755-2 minimum, D ≤ 200 mm) | 310 MPa | 260 MPa | 8 % | — |
| 2011-T3 | 379 MPa | 296 MPa | 15 % | 95 HB |
| 2017-T4 / T451 | 427 MPa | 276 MPa | 22 % | 105 HB |
| 2024-T351 | 469 MPa | 324 MPa | 19 % | 120 HB |
| 2014-T6 / T651 | 483 MPa | 414 MPa | 13 % | 135 HB |
| 7075-T6 / T651 | 572 MPa | 503 MPa | 11 % | 150 HB |
| 7075-T73 / T7351 | 503 MPa | 434 MPa | 13 % | — |
Large-diameter heat-treated bar has lower minimum properties at the centre because it cools more slowly on quenching. For diameters above about 150 mm, confirm the property guarantee and test location with us.
Round bar tempers explained
T651
As T6 but stretched about 1 – 3 % after quenching to relieve stress. Preferred for parts with heavy or asymmetric machining.
T6511
Stretched like T651 with minor straightening allowed afterwards; common on extruded 6061 and 7075 bar.
T3 / T351
Solution treated, cold worked and naturally aged. Typical for 2011 and 2024 bar; T351 is the stretched version.
T73 / T7351
Over-aged 7075 that trades some strength for much better resistance to stress-corrosion cracking.
O and H112
Annealed (O) for forming; H112 is the as-extruded condition for non-heat-treatable grades such as 5083.
Round bar standards and specifications
| Standard | Scope | Notes |
|---|---|---|
| ASTM B211 / B211M | Cold-finished bar, rod and wire | Tight-tolerance drawn bar; common for 2011, 2024, 6061 |
| ASTM B221 / B221M | Extruded bars, rods, wire, profiles and tubes | General extruded bar in all main grades |
| EN 754-1/-2/-3 | Cold-drawn rod/bar and tube | Part 2 mechanical properties, part 3 round bar tolerances |
| EN 755-1/-2/-3 | Extruded rod/bar, tube and profiles | Part 2 mechanical properties, part 3 round bar tolerances |
| SAE AMS-QQ-A-225 and AMS 4117, 4122, 4124 | Aerospace bar and rod | For example AMS 4117 (6061-T6 bar), AMS 4122/4124 (7075 bar) |
| JIS H4040 | Aluminium and aluminium alloy rods, bars and wires | Japanese projects (A6061BE, A7075BD and similar) |
| GB/T 3191 | Extruded aluminium rods and bars | Chinese national standard |
Tell us which specification your drawing calls for; mill certificates report the standard, chemistry and test results for each lot.
Round bar sizes and weight per metre
Supply range
- Extruded diameter
- about 6 – 300 mm in most grades; larger in 6061, 6082 and 7075 by special order
- Drawn diameter
- about 3 – 100 mm, with h9 to h11 type tolerances typical for precision bar
- Forged or cast bar
- Diameters to about 500 mm and above for heavy machined parts
- Imperial sizes
- 1/8 in to 12 in diameter in fractional steps
- Lengths
- 3 m, 4 m, 6 m, 12 ft random or fixed lengths; cut pieces to drawing
- Processing
- Saw cutting to length, chamfering, ultrasonic inspection on request
Weight of round bar in kg/m = 0.0021206 × d², with d in millimetres and a density of 2.70 g/cm³. 7xxx and 2xxx grades are 3 – 4 % heavier. The bar weight calculator handles any size and grade.
| Diameter (mm) | kg per metre | kg per 3 m length | kg per 6 m length |
|---|---|---|---|
| 6 | 0.08 | 0.23 | 0.46 |
| 8 | 0.14 | 0.41 | 0.81 |
| 10 | 0.21 | 0.64 | 1.27 |
| 12 | 0.31 | 0.92 | 1.83 |
| 16 | 0.54 | 1.63 | 3.26 |
| 20 | 0.85 | 2.54 | 5.09 |
| 25 | 1.33 | 3.98 | 7.95 |
| 30 | 1.91 | 5.73 | 11.45 |
| 40 | 3.39 | 10.18 | 20.36 |
| 50 | 5.30 | 15.90 | 31.81 |
| 60 | 7.63 | 22.90 | 45.80 |
| 80 | 13.57 | 40.72 | 81.43 |
| 100 | 21.21 | 63.62 | 127.23 |
| 120 | 30.54 | 91.61 | 183.22 |
| 150 | 47.71 | 143.14 | 286.28 |
| 200 | 84.82 | 254.47 | 508.94 |
| 250 | 132.54 | 397.61 | 795.22 |
| 300 | 190.85 | 572.56 | 1145.11 |
Diameter tolerance, straightness and inspection
Extruded round bar is supplied to the tolerance tables of EN 755-3 or ASTM B221 (ANSI H35.2), which widen as diameter grows. Cold-drawn bar to EN 754-3 or ASTM B211 is markedly tighter and rounder, and precision-ground bar can be held tighter still. Always check that the machining allowance on your part covers both the diameter tolerance and any bow along the length.
Quality checks
- Diameter and ovality
- Measured with micrometers at several points along the bar
- Straightness
- Checked over the full length and per metre against the standard
- Surface
- Visual inspection for die lines, pick-up and handling damage
- Internal soundness
- Ultrasonic testing to AMS-STD-2154 or EN 10308-type methods for aerospace and critical parts on request
- Certification
- EN 10204 3.1 mill test certificate with chemistry and tensile results
Machining, welding and finishing round bar
Turning
2011-T3 gives the smallest chips and highest speeds; 7075-T6, 2024-T351 and 6061-T6 also machine very well with sharp, polished carbide. 6063 and 5xxx grades are softer and more prone to built-up edge.
Drilling and threading
Use high-helix drills and through-coolant where possible. Roll-formed threads in 6061 and 7075 have better fatigue performance than cut threads.
Welding
6061, 6082 and 5083 bar weld readily by TIG or MIG. 2011, 2024 and 7075 are generally not fusion welded in structural service.
Anodising
6061, 6063 and 6082 give the most even anodic finish. 2011 and 2024 anodise with a darker, less uniform appearance; 7075 hard-anodises well.
Corrosion
5xxx and 6xxx bar suit outdoor and marine use. 2xxx and 7xxx bar need anodising, paint or cladding in corrosive environments.
Stress relief
Choose stretched tempers (T651, T6511, T351) when large amounts of metal are removed from one side or tight post-machining straightness is needed.
Where aluminium round bar is used
- Precision turned parts: connectors, valve bodies, nozzles, camera and optical parts, fasteners
- Machinery: shafts, rollers, spindles, bushings, pneumatic pistons and end caps
- Automotive and EV: brake and suspension components, sensor housings, battery connectors
- Aerospace and defence: fittings, pins, actuator parts and hardware to AMS specifications
- Marine: fittings, shackles and hardware in 5083, 6061 and 6082
- Electrical: conductor rod and terminal stock in 1xxx and 6101 alloys
- Consumer goods: bicycle and sports components, furniture and decorative rods
How to order round bar from Metline
- SpecifyGrade and temper, diameter, extruded or drawn route, length and quantity, the governing standard and any ultrasonic or special test requirement.
- QuoteWe confirm alloy, temper, tolerances, certification, packing and delivery terms (EXW, FOB, CIF or DAP) for your destination.
- ProcessBars are cut to length where ordered, checked for diameter, straightness and surface, and marked with grade, temper and lot.
- DocumentEach delivery carries a mill test certificate to EN 10204 3.1 with the cast analysis and mechanical results; third-party inspection can be arranged on request.
- ShipBundled in wooden-framed packs or crates with protective wrapping, shipped by sea or air on EXW, FOB, CIF or DAP terms.
References and standards
- ASTM B211 – Standard Specification for Aluminum and Aluminum-Alloy Rolled or Cold-Finished Bar, Rod, and Wire
- ASTM B221 – Standard Specification for Aluminum and Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes
- EN 754-2 / EN 755-2 – Cold-drawn and extruded rod/bar: mechanical properties
- The Aluminum Association – International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets)
- ASM Handbook, Volume 2 – Properties and Selection: Nonferrous Alloys and Special-Purpose Materials
Aluminium (aluminum) round bar: frequently asked questions
What is the difference between extruded and drawn aluminium round bar?
Extruded bar is formed hot through a die and covers a wide diameter range at lower cost. Drawn (cold-finished) bar is extruded and then pulled through a die cold, giving tighter diameter tolerance, better roundness and a brighter surface. Choose drawn bar for bar-fed lathes and parts that keep the bar surface.
Which aluminium round bar is easiest to machine?
2011-T3 is the classic free-machining grade, producing small broken chips at high speed. 7075-T6, 2024-T351 and 6061-T6 also machine very well. Lead-free alternatives such as 6026 are available where lead content is restricted.
How do I calculate the weight of aluminium round bar?
Multiply the diameter in millimetres squared by 0.0021206 to get kg per metre at 2.70 g/cm³. A 50 mm bar weighs about 5.30 kg/m, so a 3 m length weighs about 15.9 kg.
Is 6061 or 6082 better for round bar?
They are close substitutes. 6082 is the standard in Europe and holds strength slightly better in large diameters; 6061 is more common in the Americas and Asia and has a slightly better anodised appearance. Either suits most machined parts.
Can 7075 round bar be welded?
7075 is not considered fusion-weldable for structural use because it is prone to hot cracking and loses strength in the weld zone. Use mechanical fastening, or choose 6061 or 6082 if welding is required.
Do you supply aluminium round bar cut to length?
Yes. Round bar can be supplied in mill lengths or saw-cut to fixed lengths and pieces, with mill test certificates, and shipped worldwide.
Need aluminium round bar?
Send grade, temper, diameter, length and quantity. We will reply with availability, certification and a delivered price.
