Copper Alloy C68400-H04 vs C68400-M30
Copper Alloy · C68400 temper comparison
C68400-H04 and C68400-M30 are two conditions of the same copper alloy grade, C68400: H04 (full hard) versus M30 (as hot extruded). The chemistry is identical, so every difference below comes from the condition. C68400-H04 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 250 MPa (36.3 ksi) for C68400-M30, about 80% more; tensile strength follows at 650 MPa (94.3 ksi) vs 500 MPa (72.5 ksi). In exchange, C68400-M30 is the more ductile: elongation 26% versus 12% for C68400-H04, and C68400-H04 is harder (180 HB vs 120 HB). C68400-M30 runs hotter in service (200°C vs 175°C continuous).
C68400-H04Choose it when strength drives the design.
C68400-M30Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
C68400-H04 vs C68400-M30: 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
Reduction in Area
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 103 GPa14.9 Msi · Shear Modulus 39 GPa5.7 Msi · Bulk Modulus 110 GPa16 Msi · Poisson's Ratio 0.34
Physical
Density and transition temperatures.
Same in both: Density 8.35 g/cm³0.3 lb/in³ · Melting Point (Solidus) 865°C1,589 °F · Liquidus Temperature 890°C1,634 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Same in both: Specific Heat Capacity 380 J/kg·K0.09 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 20.5 µm/m·K11.4 µin/in·°F · Latent Heat of Fusion 190 J/g81.7 BTU/lb · Min Service Temperature -200°C-328 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.27 V · Corrosion Resistance 62 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Same in both: Castability 70 / 100 · Brazeability / Solderability 70 / 100 · Polishability 75 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 50 MJ/kg21,496 BTU/lb · Embodied Carbon (primary production) 3.4 kg CO₂/kg · Embodied Water 300 L/kg35.9 gal/lb · Typical Recycled Content 50%
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.
C68400-H04 vs C68400-M30 — frequently asked
Is C68400-H04 stronger than C68400-M30?
Yes. C68400-H04 has a typical yield strength of 450 MPa (65.3 ksi) against 250 MPa (36.3 ksi) for C68400-M30 — about 80% more. Tensile strength is 650 MPa (94.3 ksi) vs 500 MPa (72.5 ksi).
Which condition does FabDigit quote by default, H04 or M30?
H02 is the default C68400 condition in the FabDigit quote flow (neither H04 nor M30). 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 welds better, C68400-H04 or C68400-M30?
C68400-M30. Its weldability rates fair (45/100) against fair (40/100) for C68400-H04.
Ready to make it?
Upload a CAD file and FabDigit prices the part in C68400-H04 and C68400-M30 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.