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Copper Alloy ERCuAl-A2 vs ERCuAl-A3

Copper Alloy · grade comparison

Copper Alloy ERCuAl-A2 and ERCuAl-A3 are both copper alloy grades. ERCuAl-A3 is the stronger of the two: yield strength 345 MPa (50 ksi) against 270 MPa (39.2 ksi) for ERCuAl-A2, about 28% more; tensile strength follows at 690 MPa (100 ksi) vs 585 MPa (84.8 ksi). In exchange, ERCuAl-A2 is the more ductile: elongation 25% versus 8% for ERCuAl-A3, and ERCuAl-A3 is harder (210 HB vs 150 HB). ERCuAl-A2 conducts heat better (59 W/m·K vs 46 W/m·K). On the shop floor, ERCuAl-A2 welds better (very good vs good).

ERCuAl-A2Choose it when the part is bent, formed or impact-loaded, or when it will be welded.

ERCuAl-A3Choose it when strength drives the design.

ERCuAl-A2 vs ERCuAl-A3: properties

ERCuAl-A2ERCuAl-A3

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

117 GPa17 Msi
115 GPa16.7 Msi

Bulk Modulus

115 GPa16.7 Msi
110 GPa16 Msi

Tensile Strength (Ultimate)

585 MPa84.8 ksi
690 MPa100 ksi

Yield Strength (0.2% offset)

270 MPa39.2 ksi
345 MPa50 ksi

Elongation at Break

25%
8%

Shear Strength

350 MPa50.8 ksi
410 MPa59.5 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
240 MPa34.8 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
14 J10.3 ft·lbf

Hardness, Brinell

150 HB
210 HB

Hardness, Rockwell B

82 HRB
—

Hardness, Vickers

158 HV
220 HV

Reduction in Area

—
10%

Hardness, Rockwell C

—
20 HRC

Same in both: Shear Modulus 44 GPa6.4 Msi · Poisson's Ratio 0.32

Physical

Density and transition temperatures.

Density

7.58 g/cm³0.27 lb/in³
7.5 g/cm³0.27 lb/in³

Liquidus Temperature

1,046°C1,915 °F
1,050°C1,922 °F

Same in both: Melting Point (Solidus) 1,030°C1,886 °F

Thermal

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

Thermal Conductivity

59 W/m·K34.1 BTU/hr·ft·°F
46 W/m·K26.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Latent Heat of Fusion

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

Min Service Temperature

-196°C-321 °F
-100°C-148 °F

Same in both: Thermal Expansion (CTE, 20–100 °C) 16.2 µm/m·K9 µin/in·°F · Max Service Temperature (continuous) 300°C572 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

13 % IACS
9 % IACS

Electrical Resistivity

1.33×10⁻⁷ Ω·m5.24 µΩ·in
1.9×10⁻⁷ Ω·m7.48 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.31 V
-0.28 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
60 / 100

Formability (cold)

45 / 100
25 / 100

Brazeability / Solderability

35 / 100
30 / 100

Polishability

68 / 100
70 / 100

Same in both: Castability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

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

Embodied Carbon (primary production)

3.9 kg CO₂/kg
4 kg CO₂/kg

Embodied Water

250 L/kg30 gal/lb
300 L/kg35.9 gal/lb

Typical Recycled Content

35%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

77 kN·m/kg
92 kN·m/kg

Specific Stiffness (E / density)

15.4 MN·m/kg
15.3 MN·m/kg

Modulus of Resilience

312 kJ/m³
518 kJ/m³

Thermal Diffusivity

18.6 mm²/s
15.3 mm²/s

Thermal Shock Resistance Index

18
17

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-A2ERCuAl-A3

Manufacturing and finishing

CapabilityERCuAl-A2ERCuAl-A3
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 ERCuAl-A3 — frequently asked

Is ERCuAl-A3 stronger than ERCuAl-A2?

Yes. ERCuAl-A3 has a typical yield strength of 345 MPa (50 ksi) against 270 MPa (39.2 ksi) for ERCuAl-A2 — about 28% more. Tensile strength is 690 MPa (100 ksi) vs 585 MPa (84.8 ksi).

Which is cheaper, ERCuAl-A2 or ERCuAl-A3?

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 ERCuAl-A3?

ERCuAl-A2. Its weldability rates very good (72/100) against good (60/100) for ERCuAl-A3.

Ready to make it?

Upload a CAD file and FabDigit prices the part in ERCuAl-A2 and ERCuAl-A3 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.