Copper Alloy C55181 vs ERCu
Copper Alloy · grade comparison
Copper Alloy C55181 and ERCu are both copper alloy grades. C55181 is the stronger of the two: tensile strength 250 MPa (36.3 ksi) against 225 MPa (32.6 ksi) for ERCu, about 11% more. In exchange, ERCu is the more ductile: elongation 35% versus 2% for C55181, and C55181 is harder (105 HB vs 55 HB). C55181 is lighter (7.95 g/cm³ vs 8.9 g/cm³ for ERCu) and ERCu runs hotter in service (250°C vs 200°C continuous). On the shop floor, ERCu welds better (very good vs poor).
C55181Choose it when strength drives the design, or when weight is the constraint.
ERCuChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
C55181 vs ERCu: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all copper alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Tensile Strength (Ultimate)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Vickers
Bulk Modulus
Yield Strength (0.2% offset)
Reduction in Area
Charpy V-Notch Impact (RT)
Same in both: Poisson's Ratio 0.34
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Machinability Rating (AISI 1212 = 100 %)
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 3.8 kg CO₂/kg · Embodied Water 250 L/kg30 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Thermal Diffusivity
Thermal Shock Resistance Index
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.
Manufacturing and finishing
| Capability | C55181 | ERCu |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.
C55181 vs ERCu — frequently asked
Is C55181 stronger than ERCu?
Yes. C55181 has a typical tensile strength of 250 MPa (36.3 ksi) against 225 MPa (32.6 ksi) for ERCu — about 11% more.
Which is cheaper, C55181 or ERCu?
Both sit in the same relative cost tier ($$$$, 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 ERCu?
ERCu, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for C55181; for welding the order is ERCu first (very good, 78/100) then C55181 (poor, 15/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in C55181 and ERCu 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.