Copper Alloy C72500-H06 vs C72500-O61
Copper Alloy · C72500 temper comparison
C72500-H06 and C72500-O61 are two conditions of the same copper alloy grade, C72500: H06 (extra hard) versus O61 (annealed). The chemistry is identical, so every difference below comes from the condition. C72500-H06 is the stronger of the two: yield strength 605 MPa (87.7 ksi) against 150 MPa (21.8 ksi) for C72500-O61, about 4.0 times as much; tensile strength follows at 640 MPa (92.8 ksi) vs 380 MPa (55.1 ksi). In exchange, C72500-O61 is the more ductile: elongation 35% versus 4% for C72500-H06, and C72500-H06 is harder (205 HV vs 105 HV). C72500-O61 runs hotter in service (250°C vs 150°C continuous).
C72500-H06Choose it when strength drives the design.
C72500-O61Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
C72500-H06 vs C72500-O61: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 138 GPa20 Msi · Shear Modulus 52 GPa7.5 Msi · Bulk Modulus 138 GPa20 Msi · Poisson's Ratio 0.34
Physical
Density and transition temperatures.
Same in both: Density 8.89 g/cm³0.32 lb/in³ · Melting Point (Solidus) 1,060°C1,940 °F · Liquidus Temperature 1,127°C2,061 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 45 W/m·K26 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 -200°C-328 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 1.57×10⁻⁷ Ω·m6.18 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.22 V · Corrosion Resistance 70 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Formability (cold)
Same in both: Machinability Rating (AISI 1212 = 100 %) 30% · Weldability 55 / 100 · Brazeability / Solderability 90 / 100 · Polishability 80 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 62 MJ/kg26,655 BTU/lb · Embodied Carbon (primary production) 4.2 kg CO₂/kg · Embodied Water 260 L/kg31.2 gal/lb · Typical Recycled Content 30%
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.
C72500-H06 vs C72500-O61 — frequently asked
Is C72500-H06 stronger than C72500-O61?
Yes. C72500-H06 has a typical yield strength of 605 MPa (87.7 ksi) against 150 MPa (21.8 ksi) for C72500-O61 — about 4.0 times as much. Tensile strength is 640 MPa (92.8 ksi) vs 380 MPa (55.1 ksi).
Which condition does FabDigit quote by default, H06 or O61?
H02 is the default C72500 condition in the FabDigit quote flow (neither H06 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, C72500-H06 or C72500-O61?
C72500-H06, by a small margin. Both rate poor for machinability — 33/100 against 25/100 for C72500-O61.
Ready to make it?
Upload a CAD file and FabDigit prices the part in C72500-H06 and C72500-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.