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Copper Alloy C55181 vs ERCuAl-A2

Copper Alloy · grade comparison

Copper Alloy C55181 and ERCuAl-A2 are both copper alloy grades. ERCuAl-A2 is the stronger of the two: tensile strength 585 MPa (84.8 ksi) against 250 MPa (36.3 ksi) for C55181, about 134% more. ERCuAl-A2 is the more ductile: elongation 25% versus 2% for C55181, and ERCuAl-A2 is harder (150 HB vs 105 HB). ERCuAl-A2 is lighter (7.58 g/cm³ vs 7.95 g/cm³ for C55181) and ERCuAl-A2 is stiffer (117 GPa vs 110 GPa). On the shop floor, ERCuAl-A2 welds better (very good vs poor).

ERCuAl-A2Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

C55181 vs ERCuAl-A2: properties

C55181ERCuAl-A2

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

110 GPa16 Msi
117 GPa17 Msi

Shear Modulus

42 GPa6.1 Msi
44 GPa6.4 Msi

Poisson's Ratio

0.34
0.32

Tensile Strength (Ultimate)

250 MPa36.3 ksi
585 MPa84.8 ksi

Elongation at Break

2%
25%

Shear Strength

170 MPa24.7 ksi
350 MPa50.8 ksi

Fatigue Strength (Endurance Limit)

55 MPa8 ksi
200 MPa29 ksi

Hardness, Brinell

105 HB
150 HB

Hardness, Vickers

115 HV
158 HV

Bulk Modulus

—
115 GPa16.7 Msi

Yield Strength (0.2% offset)

—
270 MPa39.2 ksi

Charpy V-Notch Impact (RT)

—
40 J29.5 ft·lbf

Hardness, Rockwell B

—
82 HRB

Physical

Density and transition temperatures.

Density

7.95 g/cm³0.29 lb/in³
7.58 g/cm³0.27 lb/in³

Melting Point (Solidus)

710°C1,310 °F
1,030°C1,886 °F

Liquidus Temperature

793°C1,459 °F
1,046°C1,915 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
59 W/m·K34.1 BTU/hr·ft·°F

Specific Heat Capacity

380 J/kg·K0.09 BTU/lb·°F
419 J/kg·K0.1 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

17 µm/m·K9.4 µin/in·°F
16.2 µm/m·K9 µin/in·°F

Latent Heat of Fusion

195 J/g83.8 BTU/lb
205 J/g88.1 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
300°C572 °F

Min Service Temperature

-100°C-148 °F
-196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
13 % IACS

Electrical Resistivity

1.7×10⁻⁷ Ω·m6.69 µΩ·in
1.33×10⁻⁷ Ω·m5.24 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.25 V
-0.31 V

Corrosion Resistance

58 / 100
74 / 100

Manufacturability

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

Machinability

25 / 100
32 / 100

Weldability

15 / 100
72 / 100

Formability (cold)

20 / 100
45 / 100

Castability

70 / 100
65 / 100

Brazeability / Solderability

95 / 100
35 / 100

Polishability

40 / 100
68 / 100

Machinability Rating (AISI 1212 = 100 %)

—
30%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
58 MJ/kg24,936 BTU/lb

Embodied Carbon (primary production)

3.8 kg CO₂/kg
3.9 kg CO₂/kg

Typical Recycled Content

30%
35%

Same in both: Embodied Water 250 L/kg30 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

31 kN·m/kg
77 kN·m/kg

Specific Stiffness (E / density)

13.8 MN·m/kg
15.4 MN·m/kg

Thermal Diffusivity

14.9 mm²/s
18.6 mm²/s

Thermal Shock Resistance Index

6
18

Strength versus weight

Yield strength against density for every copper alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

501002005001,0007.588.599.5Density (g/cm³)Yield strength (MPa) — log scaleERCuAl-A2

Manufacturing and finishing

CapabilityC55181ERCuAl-A2
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

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

C55181 vs ERCuAl-A2 — frequently asked

Is ERCuAl-A2 stronger than C55181?

Yes. ERCuAl-A2 has a typical tensile strength of 585 MPa (84.8 ksi) against 250 MPa (36.3 ksi) for C55181 — about 134% more.

Which is cheaper, C55181 or ERCuAl-A2?

Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, C55181 or ERCuAl-A2?

ERCuAl-A2, by a small margin. Both rate poor for machinability — 32/100 against 25/100 for C55181; for welding the order is ERCuAl-A2 first (very good, 72/100) then C55181 (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C55181 and ERCuAl-A2 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.