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Copper Alloy C84400 vs C86800

Copper Alloy · grade comparison

Copper Alloy C84400 and C86800 are both copper alloy grades. C86800 is the stronger of the two: yield strength 290 MPa (42.1 ksi) against 110 MPa (16 ksi) for C84400, about 164% more; tensile strength follows at 565 MPa (81.9 ksi) vs 234 MPa (33.9 ksi). In exchange, C84400 is the more ductile: elongation 26% versus 20% for C86800, and C86800 is harder (150 HB vs 55 HB). C86800 is lighter (7.9 g/cm³ vs 8.8 g/cm³ for C84400) and C86800 is stiffer (105 GPa vs 95 GPa). On the shop floor, C84400 machines more easily (excellent vs fair), C86800 welds better (30 vs 20 out of 100), and C86800 sits in a lower cost tier (high, $$$$) than C84400 (specialty, $$$$$).

C84400Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

C86800Choose it when strength drives the design, or when weight is the constraint.

C84400 vs C86800: properties

C84400C86800

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

95 GPa13.8 Msi
105 GPa15.2 Msi

Shear Modulus

36 GPa5.2 Msi
39 GPa5.7 Msi

Tensile Strength (Ultimate)

234 MPa33.9 ksi
565 MPa81.9 ksi

Yield Strength (0.2% offset)

110 MPa16 ksi
290 MPa42.1 ksi

Elongation at Break

26%
20%

Compressive Strength

260 MPa37.7 ksi
600 MPa87 ksi

Shear Strength

165 MPa23.9 ksi
380 MPa55.1 ksi

Fatigue Strength (Endurance Limit)

76 MPa11 ksi
170 MPa24.7 ksi

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
24 J17.7 ft·lbf

Hardness, Brinell

55 HB
150 HB

Hardness, Rockwell B

25 HRB
80 HRB

Reduction in Area

—
20%

Hardness, Vickers

—
158 HV

Same in both: Bulk Modulus 115 GPa16.7 Msi · Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Density

8.8 g/cm³0.32 lb/in³
7.9 g/cm³0.29 lb/in³

Melting Point (Solidus)

843°C1,549 °F
875°C1,607 °F

Liquidus Temperature

954°C1,749 °F
925°C1,697 °F

Thermal

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

Thermal Conductivity

72 W/m·K41.6 BTU/hr·ft·°F
36 W/m·K20.8 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

18 µm/m·K10 µin/in·°F
20.5 µm/m·K11.4 µin/in·°F

Latent Heat of Fusion

170 J/g73.1 BTU/lb
—

Min Service Temperature

-200°C-328 °F
-100°C-148 °F

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

Electrical

Conductivity and insulation.

Electrical Conductivity

16.4 % IACS
7.5 % IACS

Electrical Resistivity

1.05×10⁻⁷ Ω·m4.13 µΩ·in
2.3×10⁻⁷ Ω·m9.06 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.3 V

Corrosion Resistance

58 / 100
62 / 100

Manufacturability

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

Machinability

90 / 100
35 / 100

Machinability Rating (AISI 1212 = 100 %)

90%
35%

Weldability

20 / 100
30 / 100

Formability (cold)

10 / 100
—

Castability

90 / 100
75 / 100

Brazeability / Solderability

80 / 100
50 / 100

Polishability

60 / 100
65 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

42 MJ/kg18,057 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

3.2 kg CO₂/kg
3.6 kg CO₂/kg

Embodied Water

250 L/kg30 gal/lb
300 L/kg35.9 gal/lb

Typical Recycled Content

85%
65%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

27 kN·m/kg
72 kN·m/kg

Specific Stiffness (E / density)

10.8 MN·m/kg
13.3 MN·m/kg

Modulus of Resilience

64 kJ/m³
400 kJ/m³

Thermal Diffusivity

21.7 mm²/s
12 mm²/s

Thermal Shock Resistance Index

10
9

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 scaleC84400C86800

Manufacturing and finishing

CapabilityC84400C86800
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 C86800 — frequently asked

Is C86800 stronger than C84400?

Yes. C86800 has a typical yield strength of 290 MPa (42.1 ksi) against 110 MPa (16 ksi) for C84400 — about 164% more. Tensile strength is 565 MPa (81.9 ksi) vs 234 MPa (33.9 ksi).

Which is cheaper, C84400 or C86800?

C86800 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 C86800?

C84400. Its machinability rates excellent (90/100) against fair (35/100) for C86800; for welding the order is C86800 first (poor, 30/100) then C84400 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C84400 and C86800 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.