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Copper Alloy C86300 vs C99750

Copper Alloy · grade comparison

Copper Alloy C86300 and C99750 are both copper alloy grades. C86300 is the stronger of the two: yield strength 470 MPa (68.2 ksi) against 234 MPa (33.9 ksi) for C99750, about 101% more; tensile strength follows at 820 MPa (119 ksi) vs 455 MPa (66 ksi). In exchange, C99750 is the more ductile: elongation 25% versus 15% for C86300, and C86300 is harder (225 HB vs 130 HB). C99750 runs hotter in service (250°C vs 200°C continuous) and C86300 conducts heat better (36 W/m·K vs 25 W/m·K). On the shop floor, C99750 machines more easily (fair vs poor), C99750 welds better (fair vs poor), and C99750 sits in a lower cost tier (high, $$$$) than C86300 (specialty, $$$$$).

C86300Choose it when strength drives the design.

C99750Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

C86300 vs C99750: properties

C86300C99750

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

103 GPa14.9 Msi
100 GPa14.5 Msi

Shear Modulus

39 GPa5.7 Msi
38 GPa5.5 Msi

Bulk Modulus

107 GPa15.5 Msi
105 GPa15.2 Msi

Poisson's Ratio

0.34
0.33

Tensile Strength (Ultimate)

820 MPa119 ksi
455 MPa66 ksi

Yield Strength (0.2% offset)

470 MPa68.2 ksi
234 MPa33.9 ksi

Elongation at Break

15%
25%

Reduction in Area

18%
—

Compressive Strength

480 MPa69.6 ksi
—

Shear Strength

540 MPa78.3 ksi
310 MPa45 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
155 MPa22.5 ksi

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

225 HB
130 HB

Hardness, Rockwell B

96 HRB
74 HRB

Physical

Density and transition temperatures.

Density

7.65 g/cm³0.28 lb/in³
7.78 g/cm³0.28 lb/in³

Melting Point (Solidus)

862°C1,584 °F
871°C1,600 °F

Liquidus Temperature

924°C1,695 °F
899°C1,650 °F

Thermal

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

Thermal Conductivity

36 W/m·K20.8 BTU/hr·ft·°F
25 W/m·K14.4 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

19.3 µm/m·K10.7 µin/in·°F
20 µm/m·K11.1 µin/in·°F

Latent Heat of Fusion

175 J/g75.2 BTU/lb
200 J/g86 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
250°C482 °F

Same in both: Min Service Temperature -100°C-148 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

8 % IACS
3.5 % IACS

Electrical Resistivity

2.16×10⁻⁷ Ω·m8.5 µΩ·in
4.9×10⁻⁷ Ω·m19.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.3 V
-0.28 V

Corrosion Resistance

45 / 100
62 / 100

Manufacturability

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

Machinability

25 / 100
35 / 100

Machinability Rating (AISI 1212 = 100 %)

25%
30%

Weldability

30 / 100
45 / 100

Formability (cold)

15 / 100
25 / 100

Castability

80 / 100
75 / 100

Brazeability / Solderability

25 / 100
45 / 100

Polishability

60 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
45 MJ/kg19,347 BTU/lb

Embodied Carbon (primary production)

3.6 kg CO₂/kg
3.2 kg CO₂/kg

Embodied Water

200 L/kg24 gal/lb
300 L/kg35.9 gal/lb

Same in both: Typical Recycled Content 70%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

107 kN·m/kg
58 kN·m/kg

Specific Stiffness (E / density)

13.5 MN·m/kg
12.9 MN·m/kg

Modulus of Resilience

1,072 kJ/m³
274 kJ/m³

Thermal Diffusivity

12.5 mm²/s
8 mm²/s

Thermal Shock Resistance Index

15
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 scaleC86300C99750

Manufacturing and finishing

CapabilityC86300C99750
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.

C86300 vs C99750 — frequently asked

Is C86300 stronger than C99750?

Yes. C86300 has a typical yield strength of 470 MPa (68.2 ksi) against 234 MPa (33.9 ksi) for C99750 — about 101% more. Tensile strength is 820 MPa (119 ksi) vs 455 MPa (66 ksi).

Which is cheaper, C86300 or C99750?

C99750 is the lower-cost material: it sits in the high tier ($$$$) while C86300 is specialty ($$$$$). 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, C86300 or C99750?

C99750. Its machinability rates fair (35/100) against poor (25/100) for C86300; for welding the order is C99750 first (fair, 45/100) then C86300 (poor, 30/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C86300 and C99750 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.