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Copper Alloy ERCuAl-A2 vs ERCuNi

Copper Alloy · grade comparison

Copper Alloy ERCuAl-A2 and ERCuNi are both copper alloy grades. ERCuAl-A2 is the stronger of the two: yield strength 270 MPa (39.2 ksi) against 220 MPa (31.9 ksi) for ERCuNi, about 23% more; tensile strength follows at 585 MPa (84.8 ksi) vs 400 MPa (58 ksi). In exchange, ERCuNi is the more ductile: elongation 32% versus 25% for ERCuAl-A2, and ERCuAl-A2 is harder (150 HB vs 90 HB). ERCuAl-A2 is lighter (7.58 g/cm³ vs 8.94 g/cm³ for ERCuNi) and ERCuNi is stiffer (152 GPa vs 117 GPa).

ERCuAl-A2Choose it when strength drives the design, or when weight is the constraint.

ERCuNiChoose it when the part is bent, formed or impact-loaded.

ERCuAl-A2 vs ERCuNi: properties

ERCuAl-A2ERCuNi

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

117 GPa17 Msi
152 GPa22 Msi

Shear Modulus

44 GPa6.4 Msi
57 GPa8.3 Msi

Bulk Modulus

115 GPa16.7 Msi
158 GPa22.9 Msi

Poisson's Ratio

0.32
0.34

Tensile Strength (Ultimate)

585 MPa84.8 ksi
400 MPa58 ksi

Yield Strength (0.2% offset)

270 MPa39.2 ksi
220 MPa31.9 ksi

Elongation at Break

25%
32%

Shear Strength

350 MPa50.8 ksi
260 MPa37.7 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
130 MPa18.9 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
90 J66.4 ft·lbf

Hardness, Brinell

150 HB
90 HB

Hardness, Rockwell B

82 HRB
52 HRB

Hardness, Vickers

158 HV
95 HV

Reduction in Area

—
45%

Physical

Density and transition temperatures.

Density

7.58 g/cm³0.27 lb/in³
8.94 g/cm³0.32 lb/in³

Melting Point (Solidus)

1,030°C1,886 °F
1,170°C2,138 °F

Liquidus Temperature

1,046°C1,915 °F
1,240°C2,264 °F

Thermal

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

Thermal Conductivity

59 W/m·K34.1 BTU/hr·ft·°F
28 W/m·K16.2 BTU/hr·ft·°F

Specific Heat Capacity

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

Latent Heat of Fusion

205 J/g88.1 BTU/lb
210 J/g90.3 BTU/lb

Max Service Temperature (continuous)

300°C572 °F
315°C599 °F

Min Service Temperature

-196°C-321 °F
-198°C-324 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 16.2 µm/m·K9 µin/in·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

13 % IACS
4.6 % IACS

Electrical Resistivity

1.33×10⁻⁷ Ω·m5.24 µΩ·in
3.75×10⁻⁷ Ω·m14.8 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.31 V
-0.27 V

Same in both: Corrosion Resistance 74 / 100

Manufacturability

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

Machinability

32 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
20%

Weldability

72 / 100
78 / 100

Formability (cold)

45 / 100
75 / 100

Castability

65 / 100
45 / 100

Brazeability / Solderability

35 / 100
70 / 100

Polishability

68 / 100
72 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

58 MJ/kg24,936 BTU/lb
78 MJ/kg33,534 BTU/lb

Embodied Carbon (primary production)

3.9 kg CO₂/kg
6.2 kg CO₂/kg

Embodied Water

250 L/kg30 gal/lb
260 L/kg31.2 gal/lb

Typical Recycled Content

35%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

77 kN·m/kg
45 kN·m/kg

Specific Stiffness (E / density)

15.4 MN·m/kg
17 MN·m/kg

Modulus of Resilience

312 kJ/m³
159 kJ/m³

Thermal Diffusivity

18.6 mm²/s
8.3 mm²/s

Thermal Shock Resistance Index

18
5

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-A2ERCuNi

Manufacturing and finishing

CapabilityERCuAl-A2ERCuNi
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.

ERCuAl-A2 vs ERCuNi — frequently asked

Is ERCuAl-A2 stronger than ERCuNi?

Yes. ERCuAl-A2 has a typical yield strength of 270 MPa (39.2 ksi) against 220 MPa (31.9 ksi) for ERCuNi — about 23% more. Tensile strength is 585 MPa (84.8 ksi) vs 400 MPa (58 ksi).

Which is cheaper, ERCuAl-A2 or ERCuNi?

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 welds better, ERCuAl-A2 or ERCuNi?

ERCuNi. Its weldability rates very good (78/100) against very good (72/100) for ERCuAl-A2.

Ready to make it?

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