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Copper Alloy C81200 vs Cu-ETP1

Copper Alloy · grade comparison

Copper Alloy C81200 and Cu-ETP1 are both copper alloy grades. Cu-ETP1 is the stronger of the two: yield strength 70 MPa (10.2 ksi) against 62 MPa (8.99 ksi) for C81200, about 13% more; tensile strength follows at 220 MPa (31.9 ksi) vs 172 MPa (24.9 ksi). Cu-ETP1 is harder — 50 HV against 46 HV for C81200 — which matters for wear surfaces and threads. Cu-ETP1 conducts heat better (394 W/m·K vs 320 W/m·K). On the shop floor, C81200 welds better (good vs fair) and Cu-ETP1 forms better (excellent vs poor).

C81200Choose it when it will be welded.

Cu-ETP1Choose it when strength drives the design, or when surface hardness matters.

C81200 vs Cu-ETP1: properties

C81200Cu-ETP1

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

112 GPa16.2 Msi
117 GPa17 Msi

Shear Modulus

42 GPa6.1 Msi
44 GPa6.4 Msi

Bulk Modulus

138 GPa20 Msi
140 GPa20.3 Msi

Tensile Strength (Ultimate)

172 MPa24.9 ksi
220 MPa31.9 ksi

Yield Strength (0.2% offset)

62 MPa9 ksi
70 MPa10.2 ksi

Reduction in Area

35%
70%

Shear Strength

125 MPa18.1 ksi
150 MPa21.8 ksi

Fatigue Strength (Endurance Limit)

62 MPa9 ksi
75 MPa10.9 ksi

Charpy V-Notch Impact (RT)

45 J33.2 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

44 HB
45 HB

Hardness, Vickers

46 HV
50 HV

Same in both: Poisson's Ratio 0.34 · Elongation at Break 40%

Physical

Density and transition temperatures.

Density

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

Same in both: Melting Point (Solidus) 1,065°C1,949 °F · Liquidus Temperature 1,083°C1,981 °F

Thermal

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

Thermal Conductivity

320 W/m·K185 BTU/hr·ft·°F
394 W/m·K228 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

17.6 µm/m·K9.8 µin/in·°F
17 µm/m·K9.4 µin/in·°F

Min Service Temperature

-200°C-328 °F
-250°C-418 °F

Same in both: Specific Heat Capacity 385 J/kg·K0.09 BTU/lb·°F · Latent Heat of Fusion 205 J/g88.1 BTU/lb · Max Service Temperature (continuous) 200°C392 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

80 % IACS
101.5 % IACS

Electrical Resistivity

2.16×10⁻⁸ Ω·m0.85 µΩ·in
1.7×10⁻⁸ Ω·m0.669 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.2 V
-0.25 V

Same in both: Corrosion Resistance 65 / 100

Manufacturability

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

Machinability

25 / 100
30 / 100

Weldability

65 / 100
50 / 100

Formability (cold)

30 / 100
95 / 100

Castability

60 / 100
45 / 100

Brazeability / Solderability

90 / 100
85 / 100

Polishability

70 / 100
80 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 20%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
53 MJ/kg22,786 BTU/lb

Embodied Water

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

Typical Recycled Content

50%
10%

Same in both: Embodied Carbon (primary production) 3.6 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

19 kN·m/kg
25 kN·m/kg

Specific Stiffness (E / density)

12.6 MN·m/kg
13.1 MN·m/kg

Modulus of Resilience

17 kJ/m³
21 kJ/m³

Thermal Diffusivity

93.3 mm²/s
114.6 mm²/s

Thermal Shock Resistance Index

28
44

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-ETP1C81200

Manufacturing and finishing

CapabilityC81200Cu-ETP1
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.

C81200 vs Cu-ETP1 — frequently asked

Is Cu-ETP1 stronger than C81200?

Yes. Cu-ETP1 has a typical yield strength of 70 MPa (10.2 ksi) against 62 MPa (8.99 ksi) for C81200 — about 13% more. Tensile strength is 220 MPa (31.9 ksi) vs 172 MPa (24.9 ksi).

Which is cheaper, C81200 or Cu-ETP1?

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, C81200 or Cu-ETP1?

Cu-ETP1, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for C81200; for welding the order is C81200 first (good, 65/100) then Cu-ETP1 (fair, 50/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C81200 and Cu-ETP1 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.