Aluminum 7108A
AA 7108A · EN AlZn5Mg1Zr, AW-7108A
7108A (AlZn5Mg1Zr, EN AW-7108A) is a copper-free Al-Zn-Mg extrusion alloy in which a zirconium addition controls recrystallization and keeps a fine grain structure.
Reference datasheet — 7108A is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the T6 condition
7108A tempers and conditions
7108A is supplied in 6 conditions, soft to hard. T6 is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Softest condition for severe forming or straightening before re-solution treatment and aging. | 90 | 200 | 20 | 50 HB | 42 % IACS |
Solution heat treated and naturally aged | Formable intermediate condition; strength continues to climb slowly at room temperature, so fabricate then artificially age. | 190 | 300 | 18 | 78 HB | 31 % IACS |
Cooled from hot working and artificially aged | Economical press-quench temper for thin-wall sections where full T6 solution treatment is not required. | 280 | 335 | 11 | 98 HB | 34 % IACS |
Slightly overaged | Choose when sustained tensile loads in humid/chloride service make SCC resistance more important than the last few percent of strength. | 300 | 350 | 12 | 100 HB | 37 % IACS |
T6Default Solution heat treated and artificially aged | Standard stocked condition for welded structural extrusions needing peak strength with good HAZ recovery. | 315 | 360 | 12 | 105 HB | 35 % IACS |
T6 with improved mechanical properties | Tightly controlled T6 aging route guaranteeing higher minimum strengths for crash and load-bearing extrusions. | 350 | 390 | 10 | 115 HB | 34 % IACS |
What is 7108A?
7108A (AlZn5Mg1Zr, EN AW-7108A) is a copper-free Al-Zn-Mg extrusion alloy in which a zirconium addition controls recrystallization and keeps a fine grain structure. It is used for welded structural extrusions, with 315 MPa yield, 360 MPa tensile, 12 % elongation and 105 HB in the default condition and a weldability score of 85/100. Service is limited to 120 °C, corrosion resistance is moderate (55/100), and formability falls to 40/100 in aged tempers. 7204 is the nearest alternative when weldability matters more than strength. 7108A has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 610°C (1,130 °F). 7108A has a yield strength of 315 MPa (45.7 ksi) and a tensile strength of 360 MPa (52.2 ksi) — stronger than 79% of aluminum grades. Elongation at break is 12% and the elastic modulus is 70 GPa (10.2 Msi).
What is 7108A used for?
- Welded structural extrusions
- Bicycle components
- Transport frames
Advantages
- High strength — 315 MPa (45.7 ksi), better than 79% of aluminum grades
- Readily welded — 85/100, better than 79% 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
7108A properties
Typical room-temperature values for 7108A-T6; bars are the position among aluminum grades.
Physical3
7108A has a density of 2.78 g/cm³ (0.1 lb/in³), heavier than 74% of aluminum grades. It melts at 610°C (1,130 °F).
Mechanical13
7108A has a yield strength of 315 MPa (45.7 ksi) and a tensile strength of 360 MPa (52.2 ksi) — stronger than 79% of aluminum grades. Elongation at break is 12% and the elastic modulus is 70 GPa (10.2 Msi).
Thermal6
7108A is rated for continuous service to 120°C (248 °F). It conducts heat at 150 W/m·K (86.7 BTU/hr·ft·°F), better than 58% of aluminum grades. Thermal expansion is 23.4 µm/m·K (13 µin/in·°F).
Electrical3
7108A conducts electricity at 35 % IACS, better than 52% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (55/100), worse than 51% of aluminum grades.
Sustainability4
Producing a kilogram of 7108A takes about 200 MJ of energy and emits 12 kg of CO₂ — less than 60% of aluminum grades. Typical recycled content is 25%.
Manufacturability8
7108A's machinability is good (58/100, worse than 54% of aluminum grades); weldability excellent (85/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. 7108A is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 7108A
Is 7108A easy to machine?
Machines cleanly in T5/T6/T66 with sharp polished-flute carbide tooling, high speed and generous coolant; annealed and T4 material tends to smear and build up on edges.
Can 7108A be welded?
Designed for MIG/TIG welding with 5356 or 5183 filler — the HAZ naturally re-ages over several weeks to recover roughly 70–80 % of parent strength; avoid excessive heat input and allow post-weld natural aging before proof loading.
Can 7108A be formed, bent or molded?
Extrude and form in O or T4; bending in T6/T66 needs generous radii (≥3–4 t) and preferably a stress-relieved section, and heavy cold work after aging risks cracking.
7108A 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 |
|---|---|---|
| ZnPrimary hardener with Mg (MgZn2) | 4.5 – 5.2 | 4.8 |
| Mg | 0.7 – 1.4 | 1 |
| ZrAl3Zr dispersoids control recrystallisation and grain size | 0.12 – 0.25 | 0.16 |
| Si | ≤ 0.1 | 0.05 |
| FeA-variant allows a higher Fe ceiling than base 7108 | ≤ 0.25 | 0.15 |
| Cumax — kept low for weldability/corrosion | ≤ 0.05 | 0.02 |
| Mn | ≤ 0.05 | 0.02 |
| Cr | ≤ 0.05 | 0.01 |
| Ti | ≤ 0.05 | 0.02 |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on 7108A?
Takes protective sulphuric anodising and powder coating well after alkaline etch and desmut; decorative bright anodising is duller than 6000 series and welds anodise a different shade.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Equivalent designations
Standards and trade names that resolve to Aluminum 7108A in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- AlZn5Mg1ZrAW-7108A
How much does 7108A cost?
7108A is a premium-cost aluminum ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
7108A — frequently asked
What is 7108A used for?
7108A is typically used for welded structural extrusions, bicycle components and transport frames. In short: weldable high-strength 7000 series; zr-refined fine grain; HAZ re-ages naturally.
What is the yield strength of 7108A?
7108A has a typical yield strength of 315 MPa (45.7 ksi) and a tensile strength of 360 MPa (52.2 ksi) — stronger than 79% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is 7108A easy to machine?
Reasonably — machinability is rated good (58/100, worse than 54% of aluminum grades). Machines cleanly in T5/T6/T66 with sharp polished-flute carbide tooling, high speed and generous coolant; annealed and T4 material tends to smear and build up on edges.
Can 7108A be welded?
Yes — weldability is rated excellent (85/100). Designed for MIG/TIG welding with 5356 or 5183 filler — the HAZ naturally re-ages over several weeks to recover roughly 70–80 % of parent strength; avoid excessive heat input and allow post-weld natural aging before proof loading.
What surface finishes work on 7108A?
Takes protective sulphuric anodising and powder coating well after alkaline etch and desmut; decorative bright anodising is duller than 6000 series and welds anodise a different shade.
Can 7108A be formed, bent or molded?
Extrude and form in O or T4; bending in T6/T66 needs generous radii (≥3–4 t) and preferably a stress-relieved section, and heavy cold work after aging risks cracking.
What is the maximum service temperature of 7108A?
7108A 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 7108A-T6 and 7108A-O?
T6 is the default condition — standard stocked condition for welded structural extrusions needing peak strength with good HAZ recovery. O: softest condition for severe forming or straightening before re-solution treatment and aging. Yield strength is 315 MPa in T6 versus 90 MPa in O.
How much does 7108A cost?
7108A is a premium-cost aluminum ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- EN 573-3 Aluminium and aluminium alloys — Chemical composition of wrought products — CEN (2019)
- EN 755-2 Aluminium and aluminium alloys — Extruded rod/bar, tube and profiles: 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)
- ASM Handbook Vol. 13B — Corrosion: Materials (Al-Zn-Mg SCC behaviour) — ASM International (2005)
- Al-Zn-Mg weldable extrusion alloy datasheets (7005/7020/7108 class) — Hydro / Constellium extrusion divisions (2022)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.