Aluminum 3105 vs 3203
Aluminum · grade comparison
Aluminum 3105 and 3203 are both aluminum grades, both corrosion resistant al. 3105 is the stronger of the two: yield strength 160 MPa (23.2 ksi) against 145 MPa (21 ksi) for 3203, about 10% more; tensile strength follows at 180 MPa (26.1 ksi) vs 150 MPa (21.8 ksi). 3105 is harder — 48 HB against 40 HB for 3203 — which matters for wear surfaces and threads.
3105Choose it when strength drives the design, or when surface hardness matters.
3105 vs 3203: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Shear Strength
Hardness, Brinell
Same in both: Elastic (Young's) Modulus 69 GPa10 Msi · Shear Modulus 26 GPa3.8 Msi · Bulk Modulus 69 GPa10 Msi · Poisson's Ratio 0.33 · Elongation at Break 8% · Fatigue Strength (Endurance Limit) 62 MPa9 ksi
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
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Min Service Temperature
Same in both: Max Service Temperature (continuous) 150°C302 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 41 % IACS · Electrical Resistivity 4.2×10⁻⁸ Ω·m1.65 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Brazeability / Solderability
Same in both: Formability (cold) 70 / 100 · Polishability 45 / 100
Sustainability
Primary-production footprint per kilogram.
Typical Recycled Content
Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb · Embodied Carbon (primary production) 12 kg CO₂/kg · 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 | 3105 | 3203 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $ Budget | $ Budget |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both are offered for Sheet metal. Both take the same 15 finishes: Anodizing Type II, Cerakote, Chem Film (Alodine), E-Coating, Electroless Nickel (EN), Electropolishing, Epoxy Coating, Gold Plating, Hard Anodize Type III w/ PTFE, Hard Anodizing Type III, Nickel Plating, PTFE Coating and 3 more.
3105 vs 3203 — frequently asked
Is 3105 stronger than 3203?
Yes. 3105 has a typical yield strength of 160 MPa (23.2 ksi) against 145 MPa (21 ksi) for 3203 — about 10% more. Tensile strength is 180 MPa (26.1 ksi) vs 150 MPa (21.8 ksi).
Which is cheaper, 3105 or 3203?
Both sit in the same relative cost tier ($, budget); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose 3105 over 3203?
Pick 3105 when strength drives the design, or when surface hardness matters.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 3105 and 3203 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.