Aluminum 6205-O (Annealed)
Temper
AA 6205 · UNS A96205
Pick for maximum formability (bending, tube necking, deep drawing) before re-solution treating and aging.
Values for the O condition
Other 6205 tempers and conditions
6205 is listed in 5 conditions; see the grade overview at 6205.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
OThis page Annealed | Pick for maximum formability (bending, tube necking, deep drawing) before re-solution treating and aging. | 55 | 115 | 28 | 30 HB | 50 % IACS |
Solution heat treated and naturally aged | Use when tubes must be mitred, bent or hydroformed after heat treatment and then artificially aged to T6. | 130 | 240 | 22 | 62 HB | 41 % IACS |
Cooled from hot working and naturally aged | Lowest-cost as-extruded condition; use when moderate strength plus some remaining bendability is enough. | 152 | 262 | 19 | 65 HB | 42 % IACS |
T5Default Cooled from hot working and artificially aged | Standard stocked extrusion temper: near-T6 strength without a separate solution treatment, so straight thin-wall tube stays dimensionally stable. | 290 | 310 | 11 | 95 HB | 44 % IACS |
Solution heat treated and artificially aged | Highest-strength condition, used for butted bicycle frame tubing and structural parts that are welded then re-heat-treated. | 300 | 330 | 12 | 100 HB | 43 % IACS |
What is 6205-O?
6205-O is 6205 in the O temper — pick for maximum formability (bending, tube necking, deep drawing) before re-solution treating and aging. 6205-O has a yield strength of 55 MPa (7.98 ksi) and a tensile strength of 115 MPa (16.7 ksi) — weaker than 94% of aluminum grades. Elongation at break is 28% and the elastic modulus is 69 GPa (10 Msi). 6205-O has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 607°C (1,125 °F). T5 is the default condition FabDigit quotes; O is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 28%, better than 96% of aluminum grades
- Forms and bends easily — 90/100, better than 93% of aluminum grades
- High service temperature — 200°C (392 °F), better than 90% of aluminum grades
- Conducts heat well — 195 W/m·K (112.7 BTU/hr·ft·°F), better than 90% of aluminum grades
- High electrical conductivity — 50 % IACS, better than 90% of aluminum grades
Limitations
- Low strength — 55 MPa (7.98 ksi), worse than 94% of aluminum grades
- Difficult to machine — 30/100, worse than 92% of aluminum grades
6205-O properties
Typical room-temperature values for 6205-O; 10 are specific to this condition. Other listed values are 6205 reference data and may not represent this condition. Bars are the position among aluminum grades.
Physical3
6205-O has a density of 2.7 g/cm³ (0.0975 lb/in³), lighter than 59% of aluminum grades. It melts at 607°C (1,125 °F).
Mechanical12
6205-O has a yield strength of 55 MPa (7.98 ksi) and a tensile strength of 115 MPa (16.7 ksi) — weaker than 94% of aluminum grades. Elongation at break is 28% and the elastic modulus is 69 GPa (10 Msi).
Thermal6
6205-O is rated for continuous service to 200°C (392 °F). It conducts heat at 195 W/m·K (112.7 BTU/hr·ft·°F), better than 90% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
6205-O conducts electricity at 50 % IACS, better than 90% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 75% of aluminum grades.
Sustainability4
Producing a kilogram of 6205-O takes about 205 MJ of energy and emits 12.5 kg of CO₂ — more than 76% of aluminum grades. Typical recycled content is 30%.
Manufacturability8
6205-O's machinability is poor (30/100, worse than 92% of aluminum grades); weldability very good (72/100); formability excellent (90/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with 6205-O
Is 6205 easy to machine?
Machines like 6061-T6 in T5/T6: sharp polished-flute carbide tools, high surface speed and flood/mist coolant to stop built-up edge; gummy and burr-prone in O/T4.
Can 6205 be welded?
Readily GTAW/GMAW welded with 4043 (or 5356 for anodized colour match); HAZ drops to roughly T4-level strength unless the part is re-solution-treated and aged.
Can 6205 be formed, bent or molded?
Extrudes well in thin, complex thin-wall sections; bend and butt tubes in O or T4 and age afterwards — cold bending in T5/T6 needs generous radii to avoid cracking.
What surface finishes work on 6205?
Excellent clear and colour anodizing with clean thin-wall surfaces; also takes chromate/chrome-free conversion coating, powder coat and mechanical polish.
6205 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 – 0.9 | 0.75 |
| Feimpurity limit | ≤ 0.7 | 0.25 |
| Cu | ≤ 0.2 | 0.05 |
| Mntight Mn limit aids extrudability/anodizing | ≤ 0.1 | 0.03 |
| Mg | 0.4 – 0.6 | 0.5 |
| Cr | 0.05 – 0.15 | 0.1 |
| Zn | ≤ 0.25 | 0.05 |
| Zrgrain-structure control, distinguishing addition | 0.05 – 0.15 | 0.1 |
| Ti | ≤ 0.15 | 0.02 |
| Others (each) | ≤ 0.05 | — |
| Others (total) | ≤ 0.15 | — |
| Al | balance | — |
6205-O — frequently asked
What is 6205-O used for?
6205-O is typically used for bicycle frame tubing, sporting goods and structural extrusions. In short: higher-strength 6000-series tube alloy; thin-wall extrusion grade; clean anodizing surface.
What is the yield strength of 6205-O?
6205-O has a typical yield strength of 55 MPa (7.98 ksi) and a tensile strength of 115 MPa (16.7 ksi) — weaker than 94% of aluminum grades. Strength varies by condition: see the 5 listed tempers.
Is 6205-O easy to machine?
Not especially — machinability is rated poor (30/100, worse than 92% of aluminum grades). Machines like 6061-T6 in T5/T6: sharp polished-flute carbide tools, high surface speed and flood/mist coolant to stop built-up edge; gummy and burr-prone in O/T4.
Can 6205-O be welded?
Yes — weldability is rated very good (72/100). Readily GTAW/GMAW welded with 4043 (or 5356 for anodized colour match); HAZ drops to roughly T4-level strength unless the part is re-solution-treated and aged.
What surface finishes work on 6205-O?
Excellent clear and colour anodizing with clean thin-wall surfaces; also takes chromate/chrome-free conversion coating, powder coat and mechanical polish.
Can 6205-O be formed, bent or molded?
Extrudes well in thin, complex thin-wall sections; bend and butt tubes in O or T4 and age afterwards — cold bending in T5/T6 needs generous radii to avoid cracking.
What is the maximum service temperature of 6205-O?
6205-O is rated for continuous use to about 200°C (392 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 6205-T5 and 6205-O?
T5 is the default condition — standard stocked extrusion temper: near-T6 strength without a separate solution treatment, so straight thin-wall tube stays dimensionally stable. O: pick for maximum formability (bending, tube necking, deep drawing) before re-solution treating and aging. Yield strength is 290 MPa in T5 versus 55 MPa in O.
Sources
- 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 and Special-Purpose Materials — ASM International (1990)
- ASTM B221 — Aluminum-Alloy Extruded Bars, Rods, Wire, Profiles, and Tubes — ASTM International (2021)
- Aluminum Standards and Data — The Aluminum Association (2017)
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.