FabDigit

Aluminum 6261

AA 6261 · UNS A96261 · EN AlMg1SiCuMn

6261 is a heat-treatable Al-Mg-Si alloy with copper and manganese additions (A96261, AlMg1SiCuMn), supplied mainly as structural extrusions and stress-relieved bar in O, H111, T4, T5, T6, T651, T66, T4510 and T6510.

Standard cost $$

Reference datasheet — 6261 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.

Values for the T6 condition

6261 tempers and conditions

6261 is supplied in 9 conditions, soft to hard. T6 is the default FabDigit quotes; the values on this page are for it.

Compare all 9 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Annealed
Pick for maximum formability before a later solution treat and age; not a structural condition.651302532 HB49 % IACS
Slightly strain hardened
Soft mill/extruded condition with incidental work hardening from handling or straightening; used where the part will be formed then heat treated.851502038 HB48 % IACS
Solution heat treated and naturally aged
Choose when bending, stretch-forming or roll-forming is needed after heat treatment, with a later T6-type ageing to recover strength.1402501868 HB39 % IACS
Solution treated, naturally aged, stress-relieved by stretching
Straight, low-residual-stress bar/tube in the formable T4 state for later forming and ageing.1402451767 HB40 % IACS
Cooled from hot working and artificially aged
Economical press-quenched temper for thin-wall profiles where full T6 strength and straightness after solution treatment are not required.250290890 HB44 % IACS
T6, stress relieved by stretching
Specify when machined parts must stay dimensionally stable after heavy stock removal from plate or heavy extrusions.2953251098 HB43 % IACS
Solution treated, stretch stress-relieved, artificially aged
Precision extruded bar/profile for machined structural parts where distortion must be minimised.2953251098 HB43 % IACS
T6Default
Solution heat treated and artificially aged
Standard structural condition for 6261 — the reason to specify this alloy over 6061/6082; use for load-bearing tubes, scaffolding and framing.30033010100 HB43 % IACS
T6 with improved mechanical properties
European extruder temper giving slightly higher guaranteed proof strength than T6 with controlled ageing; used for scaffolding and access towers.3153459105 HB43 % IACS

What is 6261?

6261 is a heat-treatable Al-Mg-Si alloy with copper and manganese additions (A96261, AlMg1SiCuMn), supplied mainly as structural extrusions and stress-relieved bar in O, H111, T4, T5, T6, T651, T66, T4510 and T6510. Engineers specify it where 6061 lacks strength: the default condition gives 300 MPa yield, 330 MPa tensile, 10 % elongation and 100 HB, with weldability rated 68 and corrosion resistance 62. The heat-affected zone softens toward T4 strength unless re-solution treated and aged, T6 formability is limited (40) and service temperature is capped near 150 °C. 6082-T6 is the nearest common substitute. 6261 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 585°C (1,085 °F). 6261 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 330 MPa (47.9 ksi) — stronger than 77% of aluminum grades. Elongation at break is 10% and the elastic modulus is 70 GPa (10.2 Msi).

What is 6261 used for?

  • marine structural sections
  • transport frames
  • structural extrusions

Advantages

  • High electrical conductivity — 43 % IACS, better than 83% of aluminum grades
  • Conducts heat well — 170 W/m·K (98.2 BTU/hr·ft·°F), better than 82% of aluminum grades
  • High strength — 300 MPa (43.5 ksi), better than 77% of aluminum grades

6261 properties

Typical room-temperature values for 6261-T6; bars are the position among aluminum grades.

Physical3

6261 has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 585°C (1,085 °F).

Density2.7 g/cm³0.1 lb/in³
Melting Point (Solidus)585°C1,085 °F
Liquidus Temperature650°C1,202 °F

Mechanical13

6261 has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 330 MPa (47.9 ksi) — stronger than 77% of aluminum grades. Elongation at break is 10% and the elastic modulus is 70 GPa (10.2 Msi).

Elastic (Young's) Modulus70 GPa10.2 Msi
Shear Modulus26 GPa3.8 Msi
Bulk Modulus76 GPa11 Msi
Poisson's Ratio0.33
Tensile Strength (Ultimate)330 MPa47.9 ksi
Yield Strength (0.2% offset)300 MPa43.5 ksi
Elongation at Break10%
Compressive Strength300 MPa43.5 ksi
Shear Strength210 MPa30.5 ksi
Fatigue Strength (Endurance Limit)97 MPa14.1 ksi
Fracture Toughness (K_IC)29 MPa·√m26.4 ksi·√in
Hardness, Brinell100 HB
Hardness, Vickers110 HV

Thermal6

6261 is rated for continuous service to 150°C (302 °F). It conducts heat at 170 W/m·K (98.2 BTU/hr·ft·°F), better than 82% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).

Thermal Conductivity170 W/m·K98.2 BTU/hr·ft·°F
Specific Heat Capacity896 J/kg·K0.21 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)23.4 µm/m·K13 µin/in·°F
Latent Heat of Fusion393 J/g169 BTU/lb
Max Service Temperature (continuous)150°C302 °F
Min Service Temperature-196°C-321 °F

Electrical3

6261 conducts electricity at 43 % IACS, better than 83% of aluminum grades.

Electrical Conductivity43 % IACS
Electrical Resistivity4×10⁻⁸ Ω·m1.57 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (62/100), better than 67% of aluminum grades.

Galvanic Potential (seawater, vs SCE)-0.83 V
Corrosion ResistanceGood62/100
Chemical Resistance SummaryGood in neutral atmospheres, fresh water and mild marine exposure with anodizing or paint; attacked by strong acids and alkalis, and Cu content raises pitting sensitivity in chloride service versus Cu-free 6000 series.

Sustainability4

Producing a kilogram of 6261 takes about 200 MJ of energy and emits 12.5 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 35%.

Embodied Energy (primary production)200 MJ/kg85,985 BTU/lb
Embodied Carbon (primary production)12.5 kg CO₂/kg
Embodied Water1,200 L/kg144 gal/lb
Typical Recycled Content35%

Manufacturability8

6261's machinability is good (55/100, worse than 59% of aluminum grades); weldability good (68/100); formability fair (40/100).

MachinabilityGood55/100
Machinability Rating (AISI 1212 = 100 %)130%
WeldabilityGood68/100
Formability (cold)Fair40/100
CastabilityFair45/100
Brazeability / SolderabilityFair35/100
PolishabilityGood60/100
Anodizing Responsegood — clear and hard anodizing both work well; the 0.15–0.40 % Cu can give a slightly darker/greyer clear film than Cu-free 6060/6063

Common Calculations5

Specific Strength (UTS / density)calculated122 kN·m/kg
Specific Stiffness (E / density)calculated25.9 MN·m/kg
Modulus of Resiliencecalculated643 kJ/m³
Thermal Diffusivitycalculated70.3 mm²/s
Thermal Shock Resistance Indexcalculated34

Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.

Strength versus weight in the aluminum family

Yield strength against density for every aluminum grade FabDigit runs. 6261 is highlighted; hover a dot for its name, or open the interactive family chart.

20501002005002.22.42.62.83Density (g/cm³)Yield strength (MPa) — log scale6261

Working with 6261

Is 6261 easy to machine?

Machines like 6061-T6: high speeds, polished-flute carbide, 3-flute cutters and coolant/lubricant to avoid built-up edge; gummy in O/T4.

Can 6261 be welded?

Readily GMAW/GTAW welded with ER4043 (crack resistance) or ER5356 (strength/anodizing match); expect HAZ strength down toward T4 levels unless post-weld solution treat and age.

Can 6261 be formed, bent or molded?

Extrudes and roll-forms well in O/T4; in T6 keep bend radii ≥3–4 t and avoid tight reverse bends — springback is high.

6261 chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
Si0.4 – 0.70.55
Feimpurity limit≤ 0.40.2
Curaises strength, slightly lowers corrosion margin0.15 – 0.40.27
Mngrain/recrystallisation control0.2 – 0.350.28
Mg0.7 – 10.85
Cr≤ 0.1
Zn≤ 0.2
Ti≤ 0.1
Others (each)0.15 % total≤ 0.05
Albalance

What surface finishes work on 6261?

Anodizes well (clear and hard coat) though the Cu content can darken clear films slightly; also takes chromate/anodic pretreat plus powder coat, and polishes to a satin finish.

Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).

Equivalent designations

Standards and trade names that resolve to Aluminum 6261 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.

UNS
A96261
EN / DIN / Werkstoff-Nr.
AlMg1SiCuMn

How much does 6261 cost?

6261 is a standard-cost aluminum ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.

6261 — frequently asked

What is 6261 used for?

6261 is typically used for marine structural sections, transport frames and structural extrusions. In short: stronger than 6061-T6; weldable structural extrusion; marine and transport 6000 series.

What is the yield strength of 6261?

6261 has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 330 MPa (47.9 ksi) — stronger than 77% of aluminum grades. Strength varies by condition: see the 9 listed tempers.

Is 6261 easy to machine?

Reasonably — machinability is rated good (55/100, worse than 59% of aluminum grades). Machines like 6061-T6: high speeds, polished-flute carbide, 3-flute cutters and coolant/lubricant to avoid built-up edge; gummy in O/T4.

Can 6261 be welded?

Yes — weldability is rated good (68/100). Readily GMAW/GTAW welded with ER4043 (crack resistance) or ER5356 (strength/anodizing match); expect HAZ strength down toward T4 levels unless post-weld solution treat and age.

What surface finishes work on 6261?

Anodizes well (clear and hard coat) though the Cu content can darken clear films slightly; also takes chromate/anodic pretreat plus powder coat, and polishes to a satin finish.

Can 6261 be formed, bent or molded?

Extrudes and roll-forms well in O/T4; in T6 keep bend radii ≥3–4 t and avoid tight reverse bends — springback is high.

What is the maximum service temperature of 6261?

6261 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between 6261-T6 and 6261-O?

T6 is the default condition — standard structural condition for 6261 — the reason to specify this alloy over 6061/6082; use for load-bearing tubes, scaffolding and framing. O: pick for maximum formability before a later solution treat and age; not a structural condition. Yield strength is 300 MPa in T6 versus 65 MPa in O.

How much does 6261 cost?

6261 is a standard-cost aluminum ($$), cheaper than about 71% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.

Sources

  1. International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
  2. EN 755-2 Aluminium and aluminium alloys — Extruded rod/bar, tube and profiles — Mechanical properties — CEN (2016)
  3. EN 573-3 Chemical composition of wrought aluminium products — CEN (2019)
  4. ASM Handbook Vol. 2: Properties and Selection — Nonferrous Alloys — ASM International (1990)
  5. ASM Handbook Vol. 13B: Corrosion — Materials — ASM International (2005)
  6. Extruded 6000-series structural profile datasheets (scaffolding/transport tempers T5/T6/T66) — European extruders (2022)

Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.