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Copper Alloy C72950 vs C74400

Copper Alloy · grade comparison

Copper Alloy C72950 and C74400 are both copper alloy grades. C72950 is the stronger of the two: yield strength 720 MPa (104 ksi) against 440 MPa (63.8 ksi) for C74400, about 64% more; tensile strength follows at 830 MPa (120 ksi) vs 515 MPa (74.7 ksi). C72950 is harder — 300 HB against 138 HB for C74400 — which matters for wear surfaces and threads. C72950 is stiffer (138 GPa vs 124 GPa) and C72950 runs hotter in service (260°C vs 200°C continuous). On the shop floor, C72950 machines more easily (very good vs poor), C74400 welds better (fair vs poor), and C74400 forms better (very good vs poor).

C72950Choose it when strength drives the design, or when surface hardness matters.

C74400Choose it when it will be welded.

C72950 vs C74400: properties

C72950C74400

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

138 GPa20 Msi
124 GPa18 Msi

Shear Modulus

52 GPa7.5 Msi
46 GPa6.7 Msi

Bulk Modulus

128 GPa18.6 Msi
130 GPa18.9 Msi

Poisson's Ratio

0.32
0.34

Tensile Strength (Ultimate)

830 MPa120 ksi
515 MPa74.7 ksi

Yield Strength (0.2% offset)

720 MPa104 ksi
440 MPa63.8 ksi

Reduction in Area

25%
—

Compressive Strength

760 MPa110 ksi
—

Shear Strength

500 MPa72.5 ksi
340 MPa49.3 ksi

Fatigue Strength (Endurance Limit)

345 MPa50 ksi
200 MPa29 ksi

Fracture Toughness (K_IC)

45 MPa·√m41 ksi·√in
—

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
—

Hardness, Brinell

300 HB
138 HB

Hardness, Rockwell C

32 HRC
—

Hardness, Vickers

320 HV
145 HV

Hardness, Rockwell B

—
75 HRB

Same in both: Elongation at Break 12%

Physical

Density and transition temperatures.

Density

8.86 g/cm³0.32 lb/in³
8.7 g/cm³0.31 lb/in³

Melting Point (Solidus)

1,040°C1,904 °F
1,020°C1,868 °F

Liquidus Temperature

1,130°C2,066 °F
1,065°C1,949 °F

Thermal

How each material carries heat and how hot it can run.

Thermal Conductivity

32 W/m·K18.5 BTU/hr·ft·°F
45 W/m·K26 BTU/hr·ft·°F

Specific Heat Capacity

380 J/kg·K0.09 BTU/lb·°F
377 J/kg·K0.09 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

16.5 µm/m·K9.2 µin/in·°F
16.2 µm/m·K9 µin/in·°F

Max Service Temperature (continuous)

260°C500 °F
200°C392 °F

Same in both: Latent Heat of Fusion 200 J/g86 BTU/lb · Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
9.8 % IACS

Electrical Resistivity

2.15×10⁻⁷ Ω·m8.46 µΩ·in
1.76×10⁻⁷ Ω·m6.93 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.25 V
-0.2 V

Corrosion Resistance

68 / 100
62 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

70 / 100
25 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
20%

Weldability

30 / 100
52 / 100

Formability (cold)

25 / 100
70 / 100

Brazeability / Solderability

60 / 100
85 / 100

Polishability

80 / 100
90 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

68 MJ/kg29,235 BTU/lb
62 MJ/kg26,655 BTU/lb

Embodied Carbon (primary production)

4.8 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

260 L/kg31.2 gal/lb
300 L/kg35.9 gal/lb

Typical Recycled Content

20%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

94 kN·m/kg
59 kN·m/kg

Specific Stiffness (E / density)

15.6 MN·m/kg
14.3 MN·m/kg

Modulus of Resilience

1,878 kJ/m³
781 kJ/m³

Thermal Diffusivity

9.5 mm²/s
13.7 mm²/s

Same in both: Thermal Shock Resistance Index 12

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.

501002005001,0007.588.599.5Density (g/cm³)Yield strength (MPa) — log scaleC74400C72950

Manufacturing and finishing

CapabilityC72950C74400
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.

C72950 vs C74400 — frequently asked

Is C72950 stronger than C74400?

Yes. C72950 has a typical yield strength of 720 MPa (104 ksi) against 440 MPa (63.8 ksi) for C74400 — about 64% more. Tensile strength is 830 MPa (120 ksi) vs 515 MPa (74.7 ksi).

Which is cheaper, C72950 or C74400?

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, C72950 or C74400?

C72950. Its machinability rates very good (70/100) against poor (25/100) for C74400; for welding the order is C74400 first (fair, 52/100) then C72950 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C72950 and C74400 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.