Copper Alloy Cu-OF vs CuNi2SiCr
Copper Alloy · grade comparison
Copper Alloy Cu-OF and CuNi2SiCr are both copper alloy grades. CuNi2SiCr is the stronger of the two: yield strength 500 MPa (72.5 ksi) against 150 MPa (21.8 ksi) for Cu-OF, about 3.3 times as much; tensile strength follows at 600 MPa (87 ksi) vs 230 MPa (33.4 ksi). In exchange, Cu-OF is the more ductile: elongation 30% versus 12% for CuNi2SiCr, and CuNi2SiCr is harder (190 HB vs 65 HB). CuNi2SiCr is stiffer (132 GPa vs 115 GPa) and CuNi2SiCr runs hotter in service (350°C vs 200°C continuous). On the shop floor, CuNi2SiCr machines more easily (fair vs poor).
Cu-OFChoose it when the part is bent, formed or impact-loaded.
CuNi2SiCrChoose it when strength drives the design, or when the part sees heat.
Cu-OF vs CuNi2SiCr: 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
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Vickers
Compressive Strength
Charpy V-Notch Impact (RT)
Hardness, Rockwell B
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)
Max Service Temperature (continuous)
Min Service Temperature
Same in both: Latent Heat of Fusion 205 J/g88.1 BTU/lb
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 25%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
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 | Cu-OF | CuNi2SiCr |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.
Cu-OF vs CuNi2SiCr — frequently asked
Is CuNi2SiCr stronger than Cu-OF?
Yes. CuNi2SiCr has a typical yield strength of 500 MPa (72.5 ksi) against 150 MPa (21.8 ksi) for Cu-OF — about 3.3 times as much. Tensile strength is 600 MPa (87 ksi) vs 230 MPa (33.4 ksi).
Which is cheaper, Cu-OF or CuNi2SiCr?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Cu-OF or CuNi2SiCr?
CuNi2SiCr. Its machinability rates fair (45/100) against poor (20/100) for Cu-OF; for welding the order is Cu-OF first (good, 55/100) then CuNi2SiCr (fair, 50/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in Cu-OF and CuNi2SiCr 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.