Copper Alloy C31600-H04 vs C31600-O61
Copper Alloy · C31600 temper comparison
C31600-H04 and C31600-O61 are two conditions of the same copper alloy grade, C31600: H04 (full hard) versus O61 (annealed). The chemistry is identical, so every difference below comes from the condition. C31600-H04 is the stronger of the two: yield strength 345 MPa (50 ksi) against 125 MPa (18.1 ksi) for C31600-O61, about 176% more; tensile strength follows at 415 MPa (60.2 ksi) vs 300 MPa (43.5 ksi). In exchange, C31600-O61 is the more ductile: elongation 40% versus 10% for C31600-H04, and C31600-H04 is harder (112 HB vs 65 HB). C31600-O61 runs hotter in service (200°C vs 175°C continuous).
C31600-H04Choose it when strength drives the design.
C31600-O61Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
C31600-H04 vs C31600-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, Brinell
Hardness, Rockwell B
Same in both: Elastic (Young's) Modulus 115 GPa16.7 Msi · Shear Modulus 43 GPa6.2 Msi · Bulk Modulus 118 GPa17.1 Msi · Poisson's Ratio 0.34
Physical
Density and transition temperatures.
Same in both: Density 8.78 g/cm³0.32 lb/in³ · Melting Point (Solidus) 1,004°C1,839 °F · Liquidus Temperature 1,030°C1,886 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 145 W/m·K83.8 BTU/hr·ft·°F · Specific Heat Capacity 377 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 18.4 µm/m·K10.2 µin/in·°F · Latent Heat of Fusion 200 J/g86 BTU/lb · Min Service Temperature -200°C-328 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Same in both: Electrical Resistivity 4.5×10⁻⁸ Ω·m1.77 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.28 V · Corrosion Resistance 60 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 20 / 100 · Brazeability / Solderability 80 / 100 · Polishability 75 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 55 MJ/kg23,646 BTU/lb · Embodied Carbon (primary production) 3.6 kg CO₂/kg · Embodied Water 300 L/kg35.9 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.
C31600-H04 vs C31600-O61 — frequently asked
Is C31600-H04 stronger than C31600-O61?
Yes. C31600-H04 has a typical yield strength of 345 MPa (50 ksi) against 125 MPa (18.1 ksi) for C31600-O61 — about 176% more. Tensile strength is 415 MPa (60.2 ksi) vs 300 MPa (43.5 ksi).
Which condition does FabDigit quote by default, H04 or O61?
H02 is the default C31600 condition in the FabDigit quote flow (neither H04 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, C31600-H04 or C31600-O61?
C31600-H04, by a small margin. Both rate very good for machinability — 82/100 against 74/100 for C31600-O61.
Ready to make it?
Upload a CAD file and FabDigit prices the part in C31600-H04 and C31600-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.