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Copper Alloy C84400 vs C99600

Copper Alloy · grade comparison

Copper Alloy C84400 and C99600 are both copper alloy grades. C99600 is the stronger of the two: yield strength 193 MPa (28 ksi) against 110 MPa (16 ksi) for C84400, about 75% more; tensile strength follows at 434 MPa (62.9 ksi) vs 234 MPa (33.9 ksi). In exchange, C84400 is the more ductile: elongation 26% versus 20% for C99600, and C99600 is harder (115 HB vs 55 HB). C99600 is lighter (7.5 g/cm³ vs 8.8 g/cm³ for C84400) and C84400 runs hotter in service (200°C vs 150°C continuous). On the shop floor, C84400 machines more easily (excellent vs poor), C99600 welds better (fair vs poor), and C99600 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 sees heat.

C99600Choose it when strength drives the design, or when weight is the constraint.

C84400 vs C99600: properties

C84400C99600

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

95 GPa13.8 Msi
96 GPa13.9 Msi

Bulk Modulus

115 GPa16.7 Msi
105 GPa15.2 Msi

Poisson's Ratio

0.34
0.33

Tensile Strength (Ultimate)

234 MPa33.9 ksi
434 MPa62.9 ksi

Yield Strength (0.2% offset)

110 MPa16 ksi
193 MPa28 ksi

Elongation at Break

26%
20%

Compressive Strength

260 MPa37.7 ksi
210 MPa30.5 ksi

Shear Strength

165 MPa23.9 ksi
290 MPa42.1 ksi

Fatigue Strength (Endurance Limit)

76 MPa11 ksi
150 MPa21.8 ksi

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

55 HB
115 HB

Hardness, Rockwell B

25 HRB
68 HRB

Same in both: Shear Modulus 36 GPa5.2 Msi

Physical

Density and transition temperatures.

Density

8.8 g/cm³0.32 lb/in³
7.5 g/cm³0.27 lb/in³

Melting Point (Solidus)

843°C1,549 °F
900°C1,652 °F

Liquidus Temperature

954°C1,749 °F
945°C1,733 °F

Thermal

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

Thermal Conductivity

72 W/m·K41.6 BTU/hr·ft·°F
16 W/m·K9.2 BTU/hr·ft·°F

Specific Heat Capacity

377 J/kg·K0.09 BTU/lb·°F
420 J/kg·K0.1 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

18 µm/m·K10 µin/in·°F
18.5 µm/m·K10.3 µin/in·°F

Latent Heat of Fusion

170 J/g73.1 BTU/lb
215 J/g92.4 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
150°C302 °F

Min Service Temperature

-200°C-328 °F
-100°C-148 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

16.4 % IACS
2.5 % IACS

Electrical Resistivity

1.05×10⁻⁷ Ω·m4.13 µΩ·in
6.9×10⁻⁷ Ω·m27.2 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.4 V

Corrosion Resistance

58 / 100
45 / 100

Manufacturability

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

Machinability

90 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

90%
30%

Weldability

20 / 100
40 / 100

Formability (cold)

10 / 100
25 / 100

Castability

90 / 100
70 / 100

Brazeability / Solderability

80 / 100
45 / 100

Polishability

60 / 100
55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

42 MJ/kg18,057 BTU/lb
60 MJ/kg25,795 BTU/lb

Embodied Carbon (primary production)

3.2 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

250 L/kg30 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

85%
40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

27 kN·m/kg
58 kN·m/kg

Specific Stiffness (E / density)

10.8 MN·m/kg
12.8 MN·m/kg

Modulus of Resilience

64 kJ/m³
194 kJ/m³

Thermal Diffusivity

21.7 mm²/s
5.1 mm²/s

Thermal Shock Resistance Index

10
4

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 scaleC84400C99600

Manufacturing and finishing

CapabilityC84400C99600
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 C99600 — frequently asked

Is C99600 stronger than C84400?

Yes. C99600 has a typical yield strength of 193 MPa (28 ksi) against 110 MPa (16 ksi) for C84400 — about 75% more. Tensile strength is 434 MPa (62.9 ksi) vs 234 MPa (33.9 ksi).

Which is cheaper, C84400 or C99600?

C99600 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 C99600?

C84400. Its machinability rates excellent (90/100) against poor (30/100) for C99600; for welding the order is C99600 first (fair, 40/100) then C84400 (poor, 20/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C84400 and C99600 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.