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Copper Alloy Cu-ETP1 vs Cu-OF1

Copper Alloy · grade comparison

Copper Alloy Cu-ETP1 and Cu-OF1 are both copper alloy grades. Cu-OF1 is the stronger of the two: yield strength 300 MPa (43.5 ksi) against 70 MPa (10.2 ksi) for Cu-ETP1, about 4.3 times as much; tensile strength follows at 350 MPa (50.8 ksi) vs 220 MPa (31.9 ksi). In exchange, Cu-ETP1 is the more ductile: elongation 40% versus 12% for Cu-OF1, and Cu-OF1 is harder (95 HB vs 45 HB). Cu-OF1 is stiffer (125 GPa vs 117 GPa) and Cu-ETP1 runs hotter in service (200°C vs 150°C continuous). On the shop floor, Cu-OF1 welds better (good vs fair).

Cu-ETP1Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Cu-OF1Choose it when strength drives the design, or when it will be welded.

Cu-ETP1 vs Cu-OF1: properties

Cu-ETP1Cu-OF1

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

117 GPa17 Msi
125 GPa18.1 Msi

Shear Modulus

44 GPa6.4 Msi
46 GPa6.7 Msi

Tensile Strength (Ultimate)

220 MPa31.9 ksi
350 MPa50.8 ksi

Yield Strength (0.2% offset)

70 MPa10.2 ksi
300 MPa43.5 ksi

Elongation at Break

40%
12%

Reduction in Area

70%
60%

Shear Strength

150 MPa21.8 ksi
200 MPa29 ksi

Fatigue Strength (Endurance Limit)

75 MPa10.9 ksi
110 MPa16 ksi

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
—

Hardness, Brinell

45 HB
95 HB

Hardness, Vickers

50 HV
105 HV

Hardness, Rockwell B

—
45 HRB

Same in both: Bulk Modulus 140 GPa20.3 Msi · Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Density

8.93 g/cm³0.32 lb/in³
8.94 g/cm³0.32 lb/in³

Melting Point (Solidus)

1,065°C1,949 °F
1,083°C1,981 °F

Same in both: Liquidus Temperature 1,083°C1,981 °F

Thermal

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

Thermal Conductivity

394 W/m·K228 BTU/hr·ft·°F
388 W/m·K224 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
150°C302 °F

Min Service Temperature

-250°C-418 °F
-269°C-452 °F

Same in both: Specific Heat Capacity 385 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 17 µm/m·K9.4 µin/in·°F · Latent Heat of Fusion 205 J/g88.1 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

101.5 % IACS
100.2 % IACS

Electrical Resistivity

1.7×10⁻⁸ Ω·m0.669 µΩ·in
1.72×10⁻⁸ Ω·m0.678 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.25 V
-0.28 V

Corrosion Resistance

65 / 100
62 / 100

Manufacturability

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

Machinability

30 / 100
27 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
25%

Weldability

50 / 100
68 / 100

Formability (cold)

95 / 100
45 / 100

Castability

45 / 100
55 / 100

Brazeability / Solderability

85 / 100
95 / 100

Polishability

80 / 100
85 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

53 MJ/kg22,786 BTU/lb
58 MJ/kg24,936 BTU/lb

Embodied Water

350 L/kg41.9 gal/lb
250 L/kg30 gal/lb

Same in both: Embodied Carbon (primary production) 3.6 kg CO₂/kg · Typical Recycled Content 10%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

25 kN·m/kg
39 kN·m/kg

Specific Stiffness (E / density)

13.1 MN·m/kg
14 MN·m/kg

Modulus of Resilience

21 kJ/m³
360 kJ/m³

Thermal Diffusivity

114.6 mm²/s
112.7 mm²/s

Thermal Shock Resistance Index

44
64

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 scaleCu-ETP1Cu-OF1

Manufacturing and finishing

CapabilityCu-ETP1Cu-OF1
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-ETP1 vs Cu-OF1 — frequently asked

Is Cu-OF1 stronger than Cu-ETP1?

Yes. Cu-OF1 has a typical yield strength of 300 MPa (43.5 ksi) against 70 MPa (10.2 ksi) for Cu-ETP1 — about 4.3 times as much. Tensile strength is 350 MPa (50.8 ksi) vs 220 MPa (31.9 ksi).

Which is cheaper, Cu-ETP1 or Cu-OF1?

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, Cu-ETP1 or Cu-OF1?

Cu-OF1. Its weldability rates good (68/100) against fair (50/100) for Cu-ETP1.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Cu-ETP1 and Cu-OF1 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.