Aluminum 6181-T4P
Temper
AA 6181 · UNS A96181 · EN AW-6181, AW 6181
T4P = 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.
Values for the T4P 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 datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Choose for maximum drawability or when the part is heat treated after forming. | 60 | 125 | 28 | 33 HB | 50 % IACS |
T4PThis page 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. | 125 | 235 | 26 | 68 HB | 42 % IACS |
Solution heat treated and naturally aged | Standard automotive body-sheet delivery condition: formable now, strengthened later by paint-bake. | 130 | 240 | 25 | 70 HB | 44 % 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. | 200 | 270 | 16 | 82 HB | 46 % IACS |
T4 + paint-bake | Represents the in-service condition of stamped body panels after the paint-bake strength increase. | 215 | 285 | 15 | 85 HB | 46 % IACS |
T6 variant, underaged | Under-aged compromise when some post-aging bending or flanging is still required. | 235 | 290 | 14 | 88 HB | 46 % IACS |
T6, heat treated by the user | Applies when the fabricator re-solutionises formed parts and ages them to T6-level properties. | 270 | 310 | 11 | 94 HB | 48 % IACS |
Solution heat treated and artificially aged | Use where full strength and dent resistance are needed and no further deep forming is required. | 275 | 315 | 11 | 95 HB | 48 % IACS |
What is 6181-T4P?
6181-T4P is 6181 in the T4P temper — pick when parts are stamped weeks after delivery and a strong paint-bake response with stable bendability is required. 6181-T4P has a yield strength of 125 MPa (18.1 ksi) and a tensile strength of 235 MPa (34.1 ksi) — weaker than 75% of aluminum grades. Elongation at break is 26% and the elastic modulus is 69 GPa (10 Msi). 6181-T4P 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
- Ductile — tolerates forming and impact — 26%, better than 94% of aluminum grades
- Forms and bends easily — 84/100, better than 91% of aluminum grades
- High electrical conductivity — 42 % IACS, better than 81% of aluminum grades
Limitations
- Limited service temperature — 100°C (212 °F), worse than 91% of aluminum grades
- Low strength — 125 MPa (18.1 ksi), worse than 75% of aluminum grades
6181-T4P properties
Typical room-temperature values for 6181-T4P; 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-T4P 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).
Mechanical11
6181-T4P has a yield strength of 125 MPa (18.1 ksi) and a tensile strength of 235 MPa (34.1 ksi) — weaker than 75% of aluminum grades. Elongation at break is 26% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
6181-T4P is rated for continuous service to 100°C (212 °F). It conducts heat at 155 W/m·K (89.6 BTU/hr·ft·°F), better than 71% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
6181-T4P conducts electricity at 42 % IACS, better than 81% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), better than 67% of aluminum grades.
Sustainability4
Producing a kilogram of 6181-T4P takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 30%.
Manufacturability6
6181-T4P's machinability is good (55/100, worse than 59% of aluminum grades); weldability very good (75/100); formability very good (84/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 6181-T4P
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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Si | 0.8 – 1.2 | 1 |
| Feimpurity limit | ≤ 0.45 | 0.25 |
| Cu | ≤ 0.1 | 0.05 |
| Mn | ≤ 0.15 | 0.07 |
| Mg | 0.6 – 1 | 0.8 |
| Cr | ≤ 0.1 | 0.02 |
| Zn | ≤ 0.2 | 0.05 |
| Ti | ≤ 0.1 | 0.02 |
| Others (each)others total 0.15 max | ≤ 0.05 | — |
| Al | balance | — |
6181-T4P — frequently asked
What is 6181-T4P used for?
6181-T4P 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-T4P?
6181-T4P has a typical yield strength of 125 MPa (18.1 ksi) and a tensile strength of 235 MPa (34.1 ksi) — weaker than 75% of aluminum grades. Strength varies by condition: see the 8 listed tempers.
Is 6181-T4P easy to machine?
Reasonably — machinability is rated good (55/100, worse than 59% 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-T4P be welded?
Yes — weldability is rated very good (75/100). 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-T4P?
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-T4P 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-T4P?
6181-T4P is rated for continuous use to about 100°C (212 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in 6181-T4P?
Yes — 6181-T4P 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
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- EN 573-3 / EN 485-2 — Aluminium and aluminium alloys: chemical composition and mechanical properties of sheet, strip and plate — CEN (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol. 13B / Vol. 19 — Corrosion and Fatigue of Aluminum Alloys — ASM International (2005)
- 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.