Copper Alloy C74500 vs C77400
Copper Alloy · grade comparison
Copper Alloy C74500 and C77400 are both copper alloy grades. C77400 is the stronger of the two: yield strength 440 MPa (63.8 ksi) against 400 MPa (58 ksi) for C74500, about 10% more. In exchange, C74500 is the more ductile: elongation 12% versus 10% for C77400, and C74500 is harder (158 HV vs 150 HV). C77400 runs hotter in service (200°C vs 180°C continuous) and C77400 conducts electricity better (11 % IACS vs 9 % IACS). On the shop floor, C77400 welds better (50 vs 40 out of 100).
C74500Choose it when the part is bent, formed or impact-loaded.
C77400Choose it when strength drives the design, or when the part sees heat.
C74500 vs C77400: 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.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Poisson's Ratio 0.33 · Shear Strength 330 MPa47.9 ksi
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Latent Heat of Fusion
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
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Weldability
Formability (cold)
Brazeability / Solderability
Polishability
Same in both: Machinability Rating (AISI 1212 = 100 %) 20%
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 40%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Same in both: Thermal Diffusivity 13.7 mm²/s · Thermal Shock Resistance Index 11
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.
Manufacturing and finishing
| Capability | C74500 | C77400 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.
C74500 vs C77400 — frequently asked
Is C77400 stronger than C74500?
Yes. C77400 has a typical yield strength of 440 MPa (63.8 ksi) against 400 MPa (58 ksi) for C74500 — about 10% more. Tensile strength is 515 MPa (74.7 ksi) vs 510 MPa (74 ksi).
Which is cheaper, C74500 or C77400?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, C74500 or C77400?
C74500, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for C77400; for welding the order is C77400 first (fair, 50/100) then C74500 (fair, 40/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in C74500 and C77400 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.