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Aluminum 3104 vs 3203

Aluminum · grade comparison

Aluminum 3104 and 3203 are both aluminum grades, both corrosion resistant al. 3104 is the stronger of the two: yield strength 275 MPa (39.9 ksi) against 145 MPa (21 ksi) for 3203, about 90% more; tensile strength follows at 295 MPa (42.8 ksi) vs 150 MPa (21.8 ksi). In exchange, 3203 is the more ductile: elongation 8% versus 3% for 3104, and 3104 is harder (82 HB vs 40 HB). 3203 runs hotter in service (150°C vs 100°C continuous). On the shop floor, 3203 machines more easily (45 vs 35 out of 100).

3104Choose it when strength drives the design.

3203Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

3104 vs 3203: properties

31043203

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

295 MPa42.8 ksi
150 MPa21.8 ksi

Yield Strength (0.2% offset)

275 MPa39.9 ksi
145 MPa21 ksi

Elongation at Break

3%
8%

Shear Strength

165 MPa23.9 ksi
97 MPa14.1 ksi

Fatigue Strength (Endurance Limit)

110 MPa16 ksi
62 MPa9 ksi

Hardness, Brinell

82 HB
40 HB

Hardness, Vickers

90 HV
—

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

Physical

Density and transition temperatures.

Density

2.72 g/cm³0.1 lb/in³
2.73 g/cm³0.1 lb/in³

Melting Point (Solidus)

629°C1,164 °F
643°C1,189 °F

Same in both: Liquidus Temperature 654°C1,209 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

162 W/m·K93.6 BTU/hr·ft·°F
159 W/m·K91.9 BTU/hr·ft·°F

Latent Heat of Fusion

396 J/g170 BTU/lb
390 J/g168 BTU/lb

Max Service Temperature (continuous)

100°C212 °F
150°C302 °F

Min Service Temperature

-196°C-321 °F
-270°C-454 °F

Same in both: Specific Heat Capacity 893 J/kg·K0.21 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 23.2 µm/m·K12.9 µin/in·°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).

Same in both: Galvanic Potential (seawater, vs SCE) -0.83 V · Corrosion Resistance 70 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

35 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
90%

Weldability

85 / 100
88 / 100

Formability (cold)

45 / 100
70 / 100

Castability

30 / 100
—

Brazeability / Solderability

35 / 100
92 / 100

Polishability

50 / 100
45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

12.5 kg CO₂/kg
12 kg CO₂/kg

Embodied Water

1,150 L/kg138 gal/lb
1,200 L/kg144 gal/lb

Typical Recycled Content

70%
25%

Same in both: Embodied Energy (primary production) 200 MJ/kg85,985 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

108 kN·m/kg
55 kN·m/kg

Specific Stiffness (E / density)

25.4 MN·m/kg
25.3 MN·m/kg

Modulus of Resilience

548 kJ/m³
152 kJ/m³

Thermal Diffusivity

66.7 mm²/s
65.2 mm²/s

Thermal Shock Resistance Index

30
15

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.

20501002005002.22.42.62.83Density (g/cm³)Yield strength (MPa) — log scale31043203

Manufacturing and finishing

Capability31043203
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.

3104 vs 3203 — frequently asked

Is 3104 stronger than 3203?

Yes. 3104 has a typical yield strength of 275 MPa (39.9 ksi) against 145 MPa (21 ksi) for 3203 — about 90% more. Tensile strength is 295 MPa (42.8 ksi) vs 150 MPa (21.8 ksi).

Which is cheaper, 3104 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.

Which is easier to machine, 3104 or 3203?

3203, by a small margin. Both rate fair for machinability — 45/100 against 35/100 for 3104.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 3104 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.