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Aluminum 6181-T61

Temper

AA 6181 · UNS A96181 · EN AW-6181, AW 6181

T61 = t6 variant, underaged

Under-aged compromise when some post-aging bending or flanging is still required.

Values for the T61 condition

Other 6181 tempers and conditions

6181 is listed in 8 conditions; see the grade overview at 6181.

Compare all 8 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Annealed
Choose for maximum drawability or when the part is heat treated after forming.601252833 HB50 % IACS
Solution treated, pre-aged/stabilised T4 for automotive stamping
Pick when parts are stamped weeks after delivery and a strong paint-bake response with stable bendability is required.1252352668 HB42 % IACS
Solution heat treated and naturally aged
Standard automotive body-sheet delivery condition: formable now, strengthened later by paint-bake.1302402570 HB44 % IACS
Solution treated and artificially aged
Mill-specified low-strength artificial aging used when better forming than T6 is needed with more strength than T4.2002701682 HB46 % IACS
T4 + paint-bake
Represents the in-service condition of stamped body panels after the paint-bake strength increase.2152851585 HB46 % IACS
T61This page
T6 variant, underaged
Under-aged compromise when some post-aging bending or flanging is still required.2352901488 HB46 % IACS
T6, heat treated by the user
Applies when the fabricator re-solutionises formed parts and ages them to T6-level properties.2703101194 HB48 % IACS
Solution heat treated and artificially aged
Use where full strength and dent resistance are needed and no further deep forming is required.2753151195 HB48 % IACS

What is 6181-T61?

6181-T61 is 6181 in the T61 temper — under-aged compromise when some post-aging bending or flanging is still required. 6181-T61 has a yield strength of 235 MPa (34.1 ksi) and a tensile strength of 290 MPa (42.1 ksi) — stronger than 61% of aluminum grades. Elongation at break is 14% and the elastic modulus is 69 GPa (10 Msi). 6181-T61 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).

Advantages

  • High electrical conductivity — 46 % IACS, better than 87% of aluminum grades
  • Conducts heat well — 180 W/m·K (104 BTU/hr·ft·°F), better than 86% of aluminum grades
  • Ductile — tolerates forming and impact — 14%, better than 81% of aluminum grades

6181-T61 properties

Typical room-temperature values for 6181-T61; 21 are specific to this condition. Other listed values are 6181 reference data and may not represent this condition. Bars are the position among aluminum grades.

Physical3

6181-T61 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

Mechanical11

6181-T61 has a yield strength of 235 MPa (34.1 ksi) and a tensile strength of 290 MPa (42.1 ksi) — stronger than 61% of aluminum grades. Elongation at break is 14% and the elastic modulus is 69 GPa (10 Msi).

Elastic (Young's) Modulus69 GPa10 Msi
Shear Modulus26 GPa3.8 Msi
Bulk Modulus69 GPa10 Msi
Poisson's Ratio0.33
Tensile Strength (Ultimate)290 MPa42.1 ksi
Yield Strength (0.2% offset)235 MPa34.1 ksi
Elongation at Break14%
Shear Strength185 MPa26.8 ksi
Fatigue Strength (Endurance Limit)95 MPa13.8 ksi
Hardness, Brinell88 HB
Hardness, Vickers93 HV

Thermal6

6181-T61 is rated for continuous service to 150°C (302 °F). It conducts heat at 180 W/m·K (104 BTU/hr·ft·°F), better than 86% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).

Thermal Conductivity180 W/m·K104 BTU/hr·ft·°F
Specific Heat Capacity900 J/kg·K0.21 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)23.4 µm/m·K13 µin/in·°F
Latent Heat of Fusion395 J/g170 BTU/lb
Max Service Temperature (continuous)150°C302 °F
Min Service Temperature-196°C-321 °F

Electrical3

6181-T61 conducts electricity at 46 % IACS, better than 87% of aluminum grades.

Electrical Conductivity46 % IACS
Electrical Resistivity3.75×10⁻⁸ Ω·m1.48 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is good (60/100), better than 62% of aluminum grades.

Galvanic Potential (seawater, vs SCE)-0.74 V
Corrosion ResistanceGood60/100
Chemical Resistance SummaryGood in neutral atmospheres, fresh water and most organics; attacked by strong acids and alkalis; Cu-bearing variants and high-Si composition make it slightly more sensitive to intergranular attack after improper aging.

Sustainability4

Producing a kilogram of 6181-T61 takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 30%.

Embodied Energy (primary production)200 MJ/kg85,985 BTU/lb
Embodied Carbon (primary production)12 kg CO₂/kg
Embodied Water1,200 L/kg144 gal/lb
Typical Recycled Content30%

Manufacturability6

6181-T61's machinability is good (65/100, better than 62% of aluminum grades); weldability very good (70/100); formability good (55/100).

MachinabilityGood65/100
WeldabilityVery good70/100
Formability (cold)Good55/100
Brazeability / SolderabilityFair40/100
PolishabilityGood60/100
Anodizing Responsegood for protective/clear-to-grey anodize; decorative bright anodizing is only fair because the high Si and Mg2Si particles give a grey-smoky tint

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with 6181-T61

Is 6181 easy to machine?

Machines easily with sharp polished-flute carbide tools and high speeds; T4 tends to smear so prefer T6/aged material or flood lubrication for fine finishes.

Can 6181 be welded?

Readily resistance-spot, laser and MIG/TIG welded with 4043 (crack resistance) or 5356 (strength/anodizing); HAZ softening means post-weld aging or joint design allowance is needed.

Can 6181 be formed, bent or molded?

Excellent stretch/deep-draw behaviour in T4 or T4P (good r-value and n-value for outer panels); avoid forming in T6 and control natural-aging time to preserve bendability.

What surface finishes work on 6181?

Takes conversion coating, e-coat and paint very well (its normal automotive route); protective anodizing is good, decorative bright anodizing gives a grey cast due to high Si.

6181 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
Si0.8 – 1.21
Feimpurity limit≤ 0.450.25
Cu≤ 0.10.05
Mn≤ 0.150.07
Mg0.6 – 10.8
Cr≤ 0.10.02
Zn≤ 0.20.05
Ti≤ 0.10.02
Others (each)others total 0.15 max≤ 0.05—
Albalance—

6181-T61 — frequently asked

What is 6181-T61 used for?

6181-T61 is typically used for automotive outer body sheet panels, door inner panels, hood and roof outer skins, hemmed closure panels, fenders and quarter panels and tailgate and deck-lid panels. In short: auto body sheet alloy.

What is the yield strength of 6181-T61?

6181-T61 has a typical yield strength of 235 MPa (34.1 ksi) and a tensile strength of 290 MPa (42.1 ksi) — stronger than 61% of aluminum grades. Strength varies by condition: see the 8 listed tempers.

Is 6181-T61 easy to machine?

Reasonably — machinability is rated good (65/100, better than 62% of aluminum grades). Machines easily with sharp polished-flute carbide tools and high speeds; T4 tends to smear so prefer T6/aged material or flood lubrication for fine finishes.

Can 6181-T61 be welded?

Yes — weldability is rated very good (70/100). Readily resistance-spot, laser and MIG/TIG welded with 4043 (crack resistance) or 5356 (strength/anodizing); HAZ softening means post-weld aging or joint design allowance is needed.

What surface finishes work on 6181-T61?

Takes conversion coating, e-coat and paint very well (its normal automotive route); protective anodizing is good, decorative bright anodizing gives a grey cast due to high Si.

Can 6181-T61 be formed, bent or molded?

Excellent stretch/deep-draw behaviour in T4 or T4P (good r-value and n-value for outer panels); avoid forming in T6 and control natural-aging time to preserve bendability.

What is the maximum service temperature of 6181-T61?

6181-T61 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.

Can FabDigit make parts in 6181-T61?

Yes — 6181-T61 is available for CNC machining and sheet metal; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.

Sources

  1. International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
  2. EN 573-3 / EN 485-2 — Aluminium and aluminium alloys: chemical composition and mechanical properties of sheet, strip and plate — CEN (2019)
  3. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
  4. ASM Handbook Vol. 13B / Vol. 19 — Corrosion and Fatigue of Aluminum Alloys — ASM International (2005)
  5. Automotive body sheet AlMgSi (6000 series) product information — Constellium / Novelis / Hydro (2022)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.