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Copper Alloy C55284 vs ERCuSi-A

Copper Alloy · grade comparison

Copper Alloy C55284 and ERCuSi-A are both copper alloy grades. ERCuSi-A is the stronger of the two: tensile strength 350 MPa (50.8 ksi) against 275 MPa (39.9 ksi) for C55284, about 27% more. ERCuSi-A is the more ductile: elongation 38% versus 6% for C55284. ERCuSi-A is stiffer (103 GPa vs 95 GPa) and C55284 conducts heat better (50 W/m·K vs 36 W/m·K). On the shop floor, ERCuSi-A welds better (excellent vs not recommended).

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

C55284 vs ERCuSi-A: properties

C55284ERCuSi-A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

95 GPa13.8 Msi
103 GPa14.9 Msi

Poisson's Ratio

0.34
0.35

Tensile Strength (Ultimate)

275 MPa39.9 ksi
350 MPa50.8 ksi

Elongation at Break

6%
38%

Shear Strength

170 MPa24.7 ksi
215 MPa31.2 ksi

Shear Modulus

—
38.5 GPa5.6 Msi

Bulk Modulus

—
115 GPa16.7 Msi

Yield Strength (0.2% offset)

—
195 MPa28.3 ksi

Reduction in Area

—
45%

Fatigue Strength (Endurance Limit)

—
145 MPa21 ksi

Charpy V-Notch Impact (RT)

—
60 J44.3 ft·lbf

Hardness, Rockwell B

—
45 HRB

Hardness, Vickers

—
90 HV

Same in both: Hardness, Brinell 85 HB

Physical

Density and transition temperatures.

Density

8.4 g/cm³0.3 lb/in³
8.53 g/cm³0.31 lb/in³

Melting Point (Solidus)

643°C1,189 °F
970°C1,778 °F

Liquidus Temperature

813°C1,495 °F
1,025°C1,877 °F

Thermal

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

Thermal Conductivity

50 W/m·K28.9 BTU/hr·ft·°F
36 W/m·K20.8 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

17 µm/m·K9.4 µin/in·°F
18 µm/m·K10 µin/in·°F

Latent Heat of Fusion

190 J/g81.7 BTU/lb
205 J/g88.1 BTU/lb

Same in both: Specific Heat Capacity 380 J/kg·K0.09 BTU/lb·°F · Max Service Temperature (continuous) 200°C392 °F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

10 % IACS
7 % IACS

Electrical Resistivity

1.7×10⁻⁷ Ω·m6.69 µΩ·in
2.46×10⁻⁷ Ω·m9.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.2 V
-0.26 V

Corrosion Resistance

55 / 100
72 / 100

Manufacturability

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

Machinability

25 / 100
33 / 100

Weldability

10 / 100
90 / 100

Formability (cold)

55 / 100
70 / 100

Castability

75 / 100
60 / 100

Brazeability / Solderability

98 / 100
92 / 100

Polishability

60 / 100
75 / 100

Machinability Rating (AISI 1212 = 100 %)

—
30%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

270 MJ/kg116,079 BTU/lb
57 MJ/kg24,506 BTU/lb

Embodied Carbon (primary production)

20 kg CO₂/kg
3.8 kg CO₂/kg

Embodied Water

400 L/kg47.9 gal/lb
320 L/kg38.3 gal/lb

Typical Recycled Content

30%
40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

33 kN·m/kg
41 kN·m/kg

Specific Stiffness (E / density)

11.3 MN·m/kg
12.1 MN·m/kg

Thermal Diffusivity

15.7 mm²/s
11.1 mm²/s

Thermal Shock Resistance Index

9
7

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 scaleERCuSi-A

Manufacturing and finishing

CapabilityC55284ERCuSi-A
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.

C55284 vs ERCuSi-A — frequently asked

Is ERCuSi-A stronger than C55284?

Yes. ERCuSi-A has a typical tensile strength of 350 MPa (50.8 ksi) against 275 MPa (39.9 ksi) for C55284 — about 27% more.

Which is cheaper, C55284 or ERCuSi-A?

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, C55284 or ERCuSi-A?

ERCuSi-A, by a small margin. Both rate poor for machinability — 33/100 against 25/100 for C55284; for welding the order is ERCuSi-A first (excellent, 90/100) then C55284 (not recommended, 10/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C55284 and ERCuSi-A 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.