Aluminum 6012-T651
Temper
AA 6012 · UNS A96012 · EN 3.0615, AlMgSiPb
T651 = t6, stress relieved by stretching
Choose for close-tolerance machined parts where distortion after heavy stock removal must be minimised.
Values for the T651 condition
Other 6012 tempers and conditions
6012 is listed in 5 conditions; see the grade overview at 6012.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition, used only as an intermediate state before forming or re-heat-treating. | 80 | 150 | 20 | 45 HB | 47 % IACS |
Solution heat treated and naturally aged | Pick when parts must be bent, staked, riveted or crimped after machining, or artificially aged later. | 150 | 255 | 16 | 70 HB | 37 % IACS |
T6Default Solution heat treated and artificially aged | Standard stocked condition for free-machining bar: peak strength plus the best chip breaking and surface finish. | 295 | 330 | 10 | 100 HB | 40 % IACS |
T651This page T6, stress relieved by stretching | Choose for close-tolerance machined parts where distortion after heavy stock removal must be minimised. | 295 | 330 | 10 | 100 HB | 40 % IACS |
Solution heat treated, cold worked and artificially aged | Cold-drawn-then-aged bar for the highest strength and hardness with very good chip control on automatic lathes. | 330 | 360 | 8 | 110 HB | 40 % IACS |
What is 6012-T651?
6012-T651 is 6012 in the T651 temper — choose for close-tolerance machined parts where distortion after heavy stock removal must be minimised. 6012-T651 has a yield strength of 295 MPa (42.8 ksi) and a tensile strength of 330 MPa (47.9 ksi) — stronger than 75% of aluminum grades. Elongation at break is 10% and the elastic modulus is 69 GPa (10 Msi). 6012-T651 has a density of 2.72 g/cm³ (0.0983 lb/in³), heavier than 57% of aluminum grades. It melts at 580°C (1,076 °F). T6 is the default condition FabDigit quotes; T651 is available on request or by drawing note.
Advantages
- Easy to machine — 96/100, better than 100% of aluminum grades
- Conducts heat well — 165 W/m·K (95.3 BTU/hr·ft·°F), better than 79% of aluminum grades
- High strength — 295 MPa (42.8 ksi), better than 75% of aluminum grades
Limitations
- Difficult to weld — 20/100, worse than 89% of aluminum grades
- Hard to polish — 45/100, worse than 76% of aluminum grades
6012-T651 properties
Typical room-temperature values for 6012-T651; 22 are specific to this condition. Other listed values are 6012 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
6012-T651 has a density of 2.72 g/cm³ (0.0983 lb/in³), heavier than 57% of aluminum grades. It melts at 580°C (1,076 °F).
Mechanical13
6012-T651 has a yield strength of 295 MPa (42.8 ksi) and a tensile strength of 330 MPa (47.9 ksi) — stronger than 75% of aluminum grades. Elongation at break is 10% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
6012-T651 is rated for continuous service to 150°C (302 °F). It conducts heat at 165 W/m·K (95.3 BTU/hr·ft·°F), better than 79% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
6012-T651 conducts electricity at 40 % IACS, better than 72% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), better than 57% of aluminum grades.
Sustainability4
Producing a kilogram of 6012-T651 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 20%.
Manufacturability8
6012-T651's machinability is excellent (96/100, better than 100% of aluminum grades); weldability poor (20/100); formability poor (20/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 6012-T651
Is 6012 easy to machine?
Outstanding for CNC/multi-spindle work: short broken chips, low built-up edge, high feeds with polished-flute carbide and Al-specific coatings; keep Pb swarf segregated for disposal/recycling.
Can 6012 be welded?
Not recommended for structural welds — Pb causes hot cracking and porosity; use mechanical joining, adhesive bonding or select 6082/6262 where welding is required.
Can 6012 be formed, bent or molded?
Formable only in O/T4; T6/T8 bar tolerates minor staking or thread rolling but sharp bends will crack, so design for machining from bar rather than bending.
What surface finishes work on 6012?
Chromate/phosphate conversion or technical hard anodize is fine; decorative clear/colour anodize looks grey and mottled from Pb particles, and electroless nickel needs careful double-zincate pretreatment.
6012 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 | 0.6 – 1.4 | 1 |
| Fe | ≤ 0.5 | 0.3 |
| Cu | ≤ 0.4 | 0.15 |
| Mn | 0.4 – 1 | 0.7 |
| Mg | 0.6 – 1.2 | 0.9 |
| Cr | ≤ 0.3 | 0.1 |
| Zn | ≤ 0.3 | 0.1 |
| Pbfree-machining addition | 0.4 – 2 | 1 |
| Bioptional, some producers add with Pb | ≤ 0.4 | 0.1 |
| Ti | ≤ 0.1 | 0.02 |
| Others (each)total 0.15 max | ≤ 0.05 | — |
| Al | balance | — |
6012-T651 — frequently asked
What is 6012-T651 used for?
6012-T651 is typically used for screw machine parts, fittings and hardware components. In short: top free-machining 6000 series; not for welded assemblies; bar-stock CNC workhorse.
What is the yield strength of 6012-T651?
6012-T651 has a typical yield strength of 295 MPa (42.8 ksi) and a tensile strength of 330 MPa (47.9 ksi) — stronger than 75% of aluminum grades. Strength varies by condition: see the 5 listed tempers.
Is 6012-T651 easy to machine?
Yes — machinability is rated excellent (96/100, better than 100% of aluminum grades). Outstanding for CNC/multi-spindle work: short broken chips, low built-up edge, high feeds with polished-flute carbide and Al-specific coatings; keep Pb swarf segregated for disposal/recycling.
Can 6012-T651 be welded?
Not readily — weldability is rated poor (20/100). Not recommended for structural welds — Pb causes hot cracking and porosity; use mechanical joining, adhesive bonding or select 6082/6262 where welding is required.
What surface finishes work on 6012-T651?
Chromate/phosphate conversion or technical hard anodize is fine; decorative clear/colour anodize looks grey and mottled from Pb particles, and electroless nickel needs careful double-zincate pretreatment.
Can 6012-T651 be formed, bent or molded?
Formable only in O/T4; T6/T8 bar tolerates minor staking or thread rolling but sharp bends will crack, so design for machining from bar rather than bending.
What is the maximum service temperature of 6012-T651?
6012-T651 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 6012-T6 and 6012-O?
T6 is the default condition — standard stocked condition for free-machining bar: peak strength plus the best chip breaking and surface finish. O: softest condition, used only as an intermediate state before forming or re-heat-treating. Yield strength is 295 MPa in T6 versus 80 MPa in O.
Sources
- EN 573-3 Aluminium and aluminium alloys — chemical composition — CEN (2019)
- EN 755-2 Aluminium extruded rod/bar — mechanical properties — CEN (2016)
- International Alloy Designations and Chemical Composition Limits for Wrought Aluminum (Teal Sheets) — The Aluminum Association (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Free-machining aluminium bar (AlMgSiPb / EN AW-6012) datasheet — European extruder/drawn-bar producers (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.