Aluminum 7N01-T651
Temper
GB 7N01 · JIS A7N01
T651 = t6, stress relieved by stretching
Plate temper for machined parts where low residual stress and dimensional stability matter.
Values for the T651 condition
Other 7N01 tempers and conditions
7N01 is listed in 9 conditions; see the grade overview at 7N01.
Compare all 9 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for severe forming or deep bending before re-solution treating and ageing. | 120 | 225 | 20 | 65 HB | 40 % IACS |
As fabricated | Mill stock for customers who will heat treat or age the parts themselves; properties are not guaranteed. | 200 | 300 | 15 | 80 HB | 33 % IACS |
Solution heat treated and naturally aged | Choose when parts must be formed or welded first and allowed to re-age naturally to useful strength. | 210 | 330 | 17 | 90 HB | 32 % IACS |
T5Default Cooled from hot working and artificially aged | Default rolling-stock extrusion condition: good strength/weldability balance with press-quench economics. | 285 | 355 | 13 | 105 HB | 35 % IACS |
Solution heat treated and overaged for stress-corrosion resistance | Use where SCC and exfoliation resistance outweigh a 10–15 % strength penalty versus T6. | 290 | 345 | 13 | 105 HB | 38 % IACS |
Overaged between T73 and T76 | Compromise temper: most of T6 strength with much of the T73 stress-corrosion benefit. | 300 | 360 | 12 | 110 HB | 37 % IACS |
Overaged for exfoliation-corrosion resistance | Select for thin sections and skins exposed to marine or de-icing environments where exfoliation is the risk. | 310 | 365 | 12 | 112 HB | 36 % IACS |
Solution heat treated and artificially aged | Pick for maximum strength in welded frames and plate parts where full solution treatment is possible. | 320 | 375 | 12 | 115 HB | 34 % IACS |
T651This page T6, stress relieved by stretching | Plate temper for machined parts where low residual stress and dimensional stability matter. | 330 | 380 | 11 | 118 HB | 34 % IACS |
What is 7N01-T651?
7N01-T651 is 7N01 in the T651 temper — plate temper for machined parts where low residual stress and dimensional stability matter. 7N01-T651 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 81% of aluminum grades. Elongation at break is 11% and the elastic modulus is 70 GPa (10.2 Msi). 7N01-T651 has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 600°C (1,112 °F). T5 is the default condition FabDigit quotes; T651 is available on request or by drawing note.
Advantages
- High strength — 330 MPa (47.9 ksi), better than 81% of aluminum grades
- Tough — resists crack growth — 30 MPa·√m (27.3 ksi·√in), better than 76% of aluminum grades
Limitations
- Limited service temperature — 120°C (248 °F), worse than 79% of aluminum grades
7N01-T651 properties
Typical room-temperature values for 7N01-T651; 21 are specific to this condition. Other listed values are 7N01 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
7N01-T651 has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 600°C (1,112 °F).
Mechanical13
7N01-T651 has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 81% of aluminum grades. Elongation at break is 11% and the elastic modulus is 70 GPa (10.2 Msi).
Thermal6
7N01-T651 is rated for continuous service to 120°C (248 °F). It conducts heat at 138 W/m·K (79.7 BTU/hr·ft·°F), worse than 55% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7N01-T651 conducts electricity at 34 % IACS, worse than 52% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is fair (46/100), worse than 59% of aluminum grades.
Sustainability4
Producing a kilogram of 7N01-T651 takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 25%.
Manufacturability8
7N01-T651's machinability is good (68/100, better than 67% of aluminum grades); weldability very good (78/100); formability fair (40/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 7N01-T651
Is 7N01 easy to machine?
Machines well in aged tempers with sharp carbide tools, high speed and generous coolant; softer T4/O tempers tend to smear and give stringy chips.
Can 7N01 be welded?
Excellent MIG/TIG weldability with ER5356 or Al-Zn-Mg filler; HAZ softens on welding but recovers most strength by natural re-ageing over weeks, so keep welded joints out of long-term wet chloride exposure unless post-weld aged.
Can 7N01 be formed, bent or molded?
Form in O or T4 and age afterwards; aged T5/T6 material has limited bend ductility and needs generous bend radii (≥3–4 t).
What surface finishes work on 7N01?
Takes clear and hard anodizing well and paints readily after chromate-free pretreatment; dyed decorative anodizing can look grey-cast compared with 6000-series alloys.
7N01 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 | ≤ 0.3 | 0.15 |
| Fe | ≤ 0.35 | 0.2 |
| Cukept low for weldability and SCC resistance | ≤ 0.2 | 0.05 |
| Mn | 0.2 – 0.7 | 0.35 |
| Mg | 1 – 2 | 1.4 |
| Cr | ≤ 0.3 | 0.1 |
| Zn | 4 – 5 | 4.5 |
| Ti | ≤ 0.2 | 0.03 |
| ZrZr+Ti total limited to 0.25 % | ≤ 0.25 | 0.15 |
| V | ≤ 0.1 | — |
| Others (each)total 0.15 % max | ≤ 0.05 | — |
| Al | balance | — |
7N01-T651 — frequently asked
What is 7N01-T651 used for?
7N01-T651 is typically used for railway car bodies, welded structural extrusions and vehicle frames. In short: weldable high-strength 7000 series; rolling-stock body alloy; HAZ re-ages naturally.
What is the yield strength of 7N01-T651?
7N01-T651 has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 380 MPa (55.1 ksi) — stronger than 81% of aluminum grades. Strength varies by condition: see the 9 listed tempers.
Is 7N01-T651 easy to machine?
Reasonably — machinability is rated good (68/100, better than 67% of aluminum grades). Machines well in aged tempers with sharp carbide tools, high speed and generous coolant; softer T4/O tempers tend to smear and give stringy chips.
Can 7N01-T651 be welded?
Yes — weldability is rated very good (78/100). Excellent MIG/TIG weldability with ER5356 or Al-Zn-Mg filler; HAZ softens on welding but recovers most strength by natural re-ageing over weeks, so keep welded joints out of long-term wet chloride exposure unless post-weld aged.
What surface finishes work on 7N01-T651?
Takes clear and hard anodizing well and paints readily after chromate-free pretreatment; dyed decorative anodizing can look grey-cast compared with 6000-series alloys.
Can 7N01-T651 be formed, bent or molded?
Form in O or T4 and age afterwards; aged T5/T6 material has limited bend ductility and needs generous bend radii (≥3–4 t).
What is the maximum service temperature of 7N01-T651?
7N01-T651 is rated for continuous use to about 120°C (248 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 7N01-T5 and 7N01-O?
T5 is the default condition — default rolling-stock extrusion condition: good strength/weldability balance with press-quench economics. O: softest condition for severe forming or deep bending before re-solution treating and ageing. Yield strength is 285 MPa in T5 versus 120 MPa in O.
Sources
- JIS H 4100 — Aluminium and aluminium alloy extruded shapes — Japanese Standards Association (2015)
- JIS H 4000 — Aluminium and aluminium alloy sheets, strips and plates — Japanese Standards Association (2014)
- JIS E 4001 / rolling stock structural material practice — Japanese Standards Association (2011)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials (Al-Zn-Mg SCC behaviour) — ASM International (2005)
- International Alloy Designations and Chemical Composition Limits (Teal Sheets) — 7020/7005 comparison — The Aluminum Association (2018)
- SMM / Mysteel aluminium extrusion price references — SMM (2026)
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.