Aluminum 8079 vs 8091
Aluminum · grade comparison
Aluminum 8079 and 8091 are both aluminum grades. 8091 is the stronger of the two: yield strength 480 MPa (69.6 ksi) against 35 MPa (5.08 ksi) for 8079, about 14 times as much; tensile strength follows at 540 MPa (78.3 ksi) vs 85 MPa (12.3 ksi). In exchange, 8079 is the more ductile: elongation 25% versus 5% for 8091, and 8091 is harder (155 HB vs 22 HB). 8091 is lighter (2.55 g/cm³ vs 2.72 g/cm³ for 8079) and 8091 is stiffer (80 GPa vs 69 GPa). On the shop floor, 8091 machines more easily (good vs poor), 8079 welds better (very good vs poor), and 8079 sits in a lower cost tier (budget, $) than 8091 (high, $$$$).
8079Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
8091Choose it when strength drives the design, or when weight is the constraint.
8079 vs 8091: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all aluminum grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Compressive Strength
Fracture Toughness (K_IC)
Hardness, Vickers
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Specific Heat Capacity 900 J/kg·K0.21 BTU/lb·°F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Water 1,200 L/kg144 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Strength versus weight
Yield strength against density for every aluminum grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 8079 | 8091 |
|---|---|---|
| Sheet metal | Yes | — |
| Default condition | — | — |
| Relative cost | $ Budget | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
| Anodizing Type II | Yes | — |
| Cerakote | Yes | — |
| Chem Film (Alodine) | Yes | — |
| E-Coating | Yes | — |
| Electropolishing | Yes | — |
| Hard Anodize Type III w/ PTFE | Yes | — |
| Hard Anodizing Type III | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
| Powder Coating | Yes | — |
They share 4 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Silver Plating.
8079 vs 8091 — frequently asked
Is 8091 stronger than 8079?
Yes. 8091 has a typical yield strength of 480 MPa (69.6 ksi) against 35 MPa (5.08 ksi) for 8079 — about 14 times as much. Tensile strength is 540 MPa (78.3 ksi) vs 85 MPa (12.3 ksi).
Which is cheaper, 8079 or 8091?
8079 is the lower-cost material: it sits in the budget tier ($) while 8091 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.
Which is easier to machine, 8079 or 8091?
8091. Its machinability rates good (65/100) against poor (30/100) for 8079; for welding the order is 8079 first (very good, 75/100) then 8091 (poor, 25/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 8079 and 8091 side by side — material, machining time, tolerance and finish in one quote. Certified material data ships with the order on request.
Typical handbook values for the conditions named above, normalised for comparison. Hardness on non-Brinell scales is converted approximately for charting only. Request certified data with your order for design-critical properties.