Copper Alloy C68800-H04 vs C68800-H08
Copper Alloy · C68800 temper comparison
C68800-H04 and C68800-H08 are two conditions of the same copper alloy grade, C68800: H04 (full hard) versus H08 (spring hard). The chemistry is identical, so every difference below comes from the condition. C68800-H08 is the stronger of the two: yield strength 745 MPa (108 ksi) against 620 MPa (89.9 ksi) for C68800-H04, about 20% more; tensile strength follows at 814 MPa (118 ksi) vs 725 MPa (105 ksi). In exchange, C68800-H04 is the more ductile: elongation 5% versus 3% for C68800-H08, and C68800-H08 is harder (230 HV vs 200 HV). C68800-H04 runs hotter in service (150°C vs 125°C continuous).
C68800-H04Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
C68800-H08Choose it when strength drives the design.
C68800-H04 vs C68800-H08: 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 117 GPa17 Msi · Shear Modulus 44 GPa6.4 Msi · Bulk Modulus 108 GPa15.7 Msi · Poisson's Ratio 0.32
Physical
Density and transition temperatures.
Same in both: Density 8.17 g/cm³0.3 lb/in³ · Melting Point (Solidus) 932°C1,710 °F · Liquidus Temperature 949°C1,740 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 71 W/m·K41 BTU/hr·ft·°F · Specific Heat Capacity 376 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.
Same in both: Electrical Conductivity 18 % IACS · Electrical Resistivity 9.6×10⁻⁸ Ω·m3.78 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.26 V · Corrosion Resistance 68 / 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 %) 40% · Weldability 25 / 100 · Castability 30 / 100 · Brazeability / Solderability 70 / 100 · Polishability 75 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 46 MJ/kg19,776 BTU/lb · Embodied Carbon (primary production) 3.1 kg CO₂/kg · Embodied Water 250 L/kg30 gal/lb · Typical Recycled Content 35%
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.
C68800-H04 vs C68800-H08 — frequently asked
Is C68800-H08 stronger than C68800-H04?
Yes. C68800-H08 has a typical yield strength of 745 MPa (108 ksi) against 620 MPa (89.9 ksi) for C68800-H04 — about 20% more. Tensile strength is 814 MPa (118 ksi) vs 725 MPa (105 ksi).
Which condition does FabDigit quote by default, H04 or H08?
H04 is the default C68800 condition in the FabDigit quote flow. 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.
When should I choose C68800-H04 over C68800-H08?
Pick C68800-H04 when the part is bent, formed or impact-loaded, or when the part sees heat. Pick C68800-H08 when strength drives the design.
Ready to make it?
Upload a CAD file and FabDigit prices the part in C68800-H04 and C68800-H08 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.