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Copper Alloy C76400-H02 vs C76400-O61

Copper Alloy · C76400 temper comparison

C76400-H02 and C76400-O61 are two conditions of the same copper alloy grade, C76400: H02 (half hard) versus O61 (annealed). The chemistry is identical, so every difference below comes from the condition. C76400-H02 is the stronger of the two: yield strength 425 MPa (61.6 ksi) against 170 MPa (24.7 ksi) for C76400-O61, about 150% more; tensile strength follows at 515 MPa (74.7 ksi) vs 390 MPa (56.6 ksi). In exchange, C76400-O61 is the more ductile: elongation 40% versus 12% for C76400-H02, and C76400-H02 is harder (145 HB vs 90 HB). C76400-O61 runs hotter in service (300°C vs 210°C continuous).

C76400-H02Choose it when strength drives the design.

C76400-O61Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

C76400-H02 vs C76400-O61: properties

C76400-H02C76400-O61

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

515 MPa74.7 ksi
390 MPa56.6 ksi

Yield Strength (0.2% offset)

425 MPa61.6 ksi
170 MPa24.7 ksi

Elongation at Break

12%
40%

Shear Strength

350 MPa50.8 ksi
275 MPa39.9 ksi

Fatigue Strength (Endurance Limit)

190 MPa27.6 ksi
150 MPa21.8 ksi

Hardness, Brinell

145 HB
90 HB

Hardness, Rockwell B

80 HRB
45 HRB

Hardness, Vickers

155 HV
95 HV

Same in both: Elastic (Young's) Modulus 125 GPa18.1 Msi · Shear Modulus 46 GPa6.7 Msi · Bulk Modulus 130 GPa18.9 Msi · Poisson's Ratio 0.35

Physical

Density and transition temperatures.

Same in both: Density 8.7 g/cm³0.31 lb/in³ · Melting Point (Solidus) 1,040°C1,904 °F · Liquidus Temperature 1,090°C1,994 °F

Thermal

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

Max Service Temperature (continuous)

210°C410 °F
300°C572 °F

Same in both: Thermal Conductivity 29 W/m·K16.8 BTU/hr·ft·°F · Specific Heat Capacity 377 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 16.2 µm/m·K9 µin/in·°F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 6 % IACS · Electrical Resistivity 2.9×10⁻⁷ Ω·m11.4 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.22 V · Corrosion Resistance 68 / 100

Manufacturability

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

Machinability

30 / 100
25 / 100

Formability (cold)

58 / 100
85 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 25% · Weldability 55 / 100 · Castability 35 / 100 · Brazeability / Solderability 80 / 100 · Polishability 85 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 78 MJ/kg33,534 BTU/lb · Embodied Carbon (primary production) 5.5 kg CO₂/kg · Embodied Water 320 L/kg38.3 gal/lb · Typical Recycled Content 40%

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 scaleC76400

C76400-H02 vs C76400-O61 — frequently asked

Is C76400-H02 stronger than C76400-O61?

Yes. C76400-H02 has a typical yield strength of 425 MPa (61.6 ksi) against 170 MPa (24.7 ksi) for C76400-O61 — about 150% more. Tensile strength is 515 MPa (74.7 ksi) vs 390 MPa (56.6 ksi).

Which condition does FabDigit quote by default, H02 or O61?

H04 is the default C76400 condition in the FabDigit quote flow (neither H02 nor O61). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.

Which is easier to machine, C76400-H02 or C76400-O61?

C76400-H02, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for C76400-O61.

Ready to make it?

Upload a CAD file and FabDigit prices the part in C76400-H02 and C76400-O61 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.