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Aluminum A6061-RAM2 vs AlSi9Cu3

Aluminum · grade comparison

Aluminum A6061-RAM2 and AlSi9Cu3 are both aluminum grades. A6061-RAM2 is the stronger of the two: yield strength 330 MPa (47.9 ksi) against 165 MPa (23.9 ksi) for AlSi9Cu3, about 100% more; tensile strength follows at 370 MPa (53.7 ksi) vs 300 MPa (43.5 ksi). A6061-RAM2 is the more ductile: elongation 9% versus 2% for AlSi9Cu3, and A6061-RAM2 is harder (105 HB vs 85 HB). A6061-RAM2 conducts heat better (155 W/m·K vs 110 W/m·K). On the shop floor, A6061-RAM2 welds better (good vs poor) and AlSi9Cu3 sits in a lower cost tier (standard, $$) than A6061-RAM2 (high, $$$$).

A6061-RAM2Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

AlSi9Cu3Choose it when cost is the deciding factor.

A6061-RAM2 vs AlSi9Cu3: properties

A6061-RAM2AlSi9Cu3

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

73 GPa10.6 Msi
75 GPa10.9 Msi

Shear Modulus

26 GPa3.8 Msi
28 GPa4.1 Msi

Bulk Modulus

69 GPa10 Msi
73 GPa10.6 Msi

Tensile Strength (Ultimate)

370 MPa53.7 ksi
300 MPa43.5 ksi

Yield Strength (0.2% offset)

330 MPa47.9 ksi
165 MPa23.9 ksi

Elongation at Break

9%
2%

Compressive Strength

335 MPa48.6 ksi
—

Shear Strength

220 MPa31.9 ksi
190 MPa27.6 ksi

Fatigue Strength (Endurance Limit)

100 MPa14.5 ksi
95 MPa13.8 ksi

Fracture Toughness (K_IC)

27 MPa·√m24.6 ksi·√in
16 MPa·√m14.6 ksi·√in

Hardness, Brinell

105 HB
85 HB

Hardness, Rockwell B

60 HRB
—

Hardness, Vickers

115 HV
90 HV

Charpy V-Notch Impact (RT)

—
2 J1.5 ft·lbf

Same in both: Poisson's Ratio 0.33

Physical

Density and transition temperatures.

Density

2.71 g/cm³0.1 lb/in³
2.75 g/cm³0.1 lb/in³

Melting Point (Solidus)

582°C1,080 °F
515°C959 °F

Liquidus Temperature

652°C1,206 °F
595°C1,103 °F

Thermal

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

Thermal Conductivity

155 W/m·K89.6 BTU/hr·ft·°F
110 W/m·K63.6 BTU/hr·ft·°F

Specific Heat Capacity

896 J/kg·K0.21 BTU/lb·°F
880 J/kg·K0.21 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

23.2 µm/m·K12.9 µin/in·°F
21 µm/m·K11.7 µin/in·°F

Latent Heat of Fusion

400 J/g172 BTU/lb
390 J/g168 BTU/lb

Min Service Temperature

-196°C-321 °F
-100°C-148 °F

Same in both: Max Service Temperature (continuous) 150°C302 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

40 % IACS
24 % IACS

Electrical Resistivity

4.3×10⁻⁸ Ω·m1.69 µΩ·in
7.2×10⁻⁸ Ω·m2.83 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

60 / 100
38 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.78 V

Manufacturability

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

Machinability

65 / 100
62 / 100

Machinability Rating (AISI 1212 = 100 %)

130%
70%

Weldability

65 / 100
20 / 100

Formability (cold)

30 / 100
8 / 100

Brazeability / Solderability

45 / 100
20 / 100

Polishability

60 / 100
40 / 100

Castability

—
95 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

250 MJ/kg107,481 BTU/lb
190 MJ/kg81,685 BTU/lb

Embodied Carbon (primary production)

16 kg CO₂/kg
12.5 kg CO₂/kg

Typical Recycled Content

10%
85%

Same in both: Embodied Water 1,200 L/kg144 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

137 kN·m/kg
109 kN·m/kg

Specific Stiffness (E / density)

26.9 MN·m/kg
27.3 MN·m/kg

Modulus of Resilience

746 kJ/m³
182 kJ/m³

Thermal Diffusivity

63.8 mm²/s
45.5 mm²/s

Thermal Shock Resistance Index

34
21

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 scaleAlSi9Cu3A6061-RAM2

Manufacturing and finishing

CapabilityA6061-RAM2AlSi9Cu3
Default condition——
Relative cost$$$$ High$$ Standard
Min. machined wall——
Best machined surface——

Both take the same 4 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Silver Plating.

A6061-RAM2 vs AlSi9Cu3 — frequently asked

Is A6061-RAM2 stronger than AlSi9Cu3?

Yes. A6061-RAM2 has a typical yield strength of 330 MPa (47.9 ksi) against 165 MPa (23.9 ksi) for AlSi9Cu3 — about 100% more. Tensile strength is 370 MPa (53.7 ksi) vs 300 MPa (43.5 ksi).

Which is cheaper, A6061-RAM2 or AlSi9Cu3?

AlSi9Cu3 is the lower-cost material: it sits in the standard tier ($$) while A6061-RAM2 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, A6061-RAM2 or AlSi9Cu3?

A6061-RAM2. Its weldability rates good (65/100) against poor (20/100) for AlSi9Cu3.

Ready to make it?

Upload a CAD file and FabDigit prices the part in A6061-RAM2 and AlSi9Cu3 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.