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Copper Alloy C84400 vs C87400

Copper Alloy · grade comparison

Copper Alloy C84400 and C87400 are both copper alloy grades. C87400 is the stronger of the two: yield strength 165 MPa (23.9 ksi) against 110 MPa (16 ksi) for C84400, about 50% more; tensile strength follows at 379 MPa (55 ksi) vs 234 MPa (33.9 ksi). C87400 is the more ductile: elongation 30% versus 26% for C84400, and C87400 is harder (70 HB vs 55 HB). C87400 is lighter (8.3 g/cm³ vs 8.8 g/cm³ for C84400) and C87400 is stiffer (100 GPa vs 95 GPa). On the shop floor, C84400 machines more easily (excellent vs fair), C87400 welds better (very good vs poor), and C87400 sits in a lower cost tier (high, $$$$) than C84400 (specialty, $$$$$).

C84400Choose it when the part is machined in volume.

C87400Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

C84400 vs C87400: properties

C84400C87400

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

95 GPa13.8 Msi
100 GPa14.5 Msi

Shear Modulus

36 GPa5.2 Msi
37 GPa5.4 Msi

Bulk Modulus

115 GPa16.7 Msi
104 GPa15.1 Msi

Tensile Strength (Ultimate)

234 MPa33.9 ksi
379 MPa55 ksi

Yield Strength (0.2% offset)

110 MPa16 ksi
165 MPa23.9 ksi

Elongation at Break

26%
30%

Compressive Strength

260 MPa37.7 ksi
—

Shear Strength

165 MPa23.9 ksi
255 MPa37 ksi

Fatigue Strength (Endurance Limit)

76 MPa11 ksi
110 MPa16 ksi

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

55 HB
70 HB

Hardness, Rockwell B

25 HRB
30 HRB

Reduction in Area

—
25%

Hardness, Vickers

—
74 HV

Same in both: Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Density

8.8 g/cm³0.32 lb/in³
8.3 g/cm³0.3 lb/in³

Melting Point (Solidus)

843°C1,549 °F
821°C1,510 °F

Liquidus Temperature

954°C1,749 °F
917°C1,683 °F

Thermal

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

Thermal Conductivity

72 W/m·K41.6 BTU/hr·ft·°F
28.5 W/m·K16.5 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

18 µm/m·K10 µin/in·°F
19.6 µm/m·K10.9 µin/in·°F

Latent Heat of Fusion

170 J/g73.1 BTU/lb
195 J/g83.8 BTU/lb

Min Service Temperature

-200°C-328 °F
-196°C-321 °F

Same in both: Max Service Temperature (continuous) 200°C392 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

16.4 % IACS
6.7 % IACS

Electrical Resistivity

1.05×10⁻⁷ Ω·m4.13 µΩ·in
2.57×10⁻⁷ Ω·m10.1 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.26 V

Corrosion Resistance

58 / 100
70 / 100

Manufacturability

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

Machinability

90 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

90%
50%

Weldability

20 / 100
75 / 100

Formability (cold)

10 / 100
25 / 100

Castability

90 / 100
85 / 100

Brazeability / Solderability

80 / 100
60 / 100

Polishability

60 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

42 MJ/kg18,057 BTU/lb
50 MJ/kg21,496 BTU/lb

Embodied Carbon (primary production)

3.2 kg CO₂/kg
3.5 kg CO₂/kg

Typical Recycled Content

85%
75%

Same in both: Embodied Water 250 L/kg30 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

27 kN·m/kg
46 kN·m/kg

Specific Stiffness (E / density)

10.8 MN·m/kg
12 MN·m/kg

Modulus of Resilience

64 kJ/m³
136 kJ/m³

Thermal Diffusivity

21.7 mm²/s
9.1 mm²/s

Thermal Shock Resistance Index

10
6

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 scaleC84400C87400

Manufacturing and finishing

CapabilityC84400C87400
CNC machiningYes—
Default conditionAs Cast—
Relative cost$$$$$ Specialty$$$$ High
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
Chrome PlatingYes—
ElectropolishingYes—
Nickel PlatingYes—
PaintingYes—
Tin PlatingYes—

They share 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.

C84400 vs C87400 — frequently asked

Is C87400 stronger than C84400?

Yes. C87400 has a typical yield strength of 165 MPa (23.9 ksi) against 110 MPa (16 ksi) for C84400 — about 50% more. Tensile strength is 379 MPa (55 ksi) vs 234 MPa (33.9 ksi).

Which is cheaper, C84400 or C87400?

C87400 is the lower-cost material: it sits in the high tier ($$$$) while C84400 is specialty ($$$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, C84400 or C87400?

C84400. Its machinability rates excellent (90/100) against fair (50/100) for C87400; for welding the order is C87400 first (very good, 75/100) then C84400 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C84400 and C87400 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.