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Copper Alloy C51900 vs C65100

Copper Alloy · grade comparison

Copper Alloy C51900 and C65100 are both copper alloy grades. C51900 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 380 MPa (55.1 ksi) for C65100, about 18% more; tensile strength follows at 520 MPa (75.4 ksi) vs 455 MPa (66 ksi). C51900 is the more ductile: elongation 20% versus 13% for C65100. C51900 runs hotter in service (200°C vs 180°C continuous) and C51900 conducts heat better (67 W/m·K vs 57 W/m·K). On the shop floor, C65100 welds better (excellent vs fair) and C65100 sits in a lower cost tier (high, $$$$) than C51900 (specialty, $$$$$).

C51900Choose it when strength drives the design, or when the part is bent, formed or impact-loaded.

C65100Choose it when it will be welded, or when cost is the deciding factor.

C51900 vs C65100: properties

C51900C65100

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

115 GPa16.7 Msi
117 GPa17 Msi

Shear Modulus

43 GPa6.2 Msi
44 GPa6.4 Msi

Bulk Modulus

120 GPa17.4 Msi
122 GPa17.7 Msi

Tensile Strength (Ultimate)

520 MPa75.4 ksi
455 MPa66 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
380 MPa55.1 ksi

Elongation at Break

20%
13%

Reduction in Area

35%
50%

Compressive Strength

450 MPa65.3 ksi
—

Shear Strength

340 MPa49.3 ksi
285 MPa41.3 ksi

Fatigue Strength (Endurance Limit)

200 MPa29 ksi
190 MPa27.6 ksi

Hardness, Brinell

155 HB
150 HB

Hardness, Rockwell B

78 HRB
82 HRB

Hardness, Vickers

165 HV
158 HV

Charpy V-Notch Impact (RT)

—
55 J40.6 ft·lbf

Same in both: Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Density

8.8 g/cm³0.32 lb/in³
8.75 g/cm³0.32 lb/in³

Melting Point (Solidus)

910°C1,670 °F
1,030°C1,886 °F

Liquidus Temperature

1,040°C1,904 °F
1,060°C1,940 °F

Thermal

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

Thermal Conductivity

67 W/m·K38.7 BTU/hr·ft·°F
57 W/m·K32.9 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)

18.5 µm/m·K10.3 µin/in·°F
17.9 µm/m·K9.9 µin/in·°F

Latent Heat of Fusion

175 J/g75.2 BTU/lb
205 J/g88.1 BTU/lb

Max Service Temperature (continuous)

200°C392 °F
180°C356 °F

Same in both: Min Service Temperature -200°C-328 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

15 % IACS
12 % IACS

Electrical Resistivity

1.15×10⁻⁷ Ω·m4.53 µΩ·in
1.44×10⁻⁷ Ω·m5.67 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.27 V

Same in both: Corrosion Resistance 70 / 100

Manufacturability

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

Machinability

25 / 100
30 / 100

Machinability Rating (AISI 1212 = 100 %)

20%
30%

Weldability

45 / 100
92 / 100

Same in both: Formability (cold) 55 / 100 · Brazeability / Solderability 90 / 100 · Polishability 80 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

62 MJ/kg26,655 BTU/lb
58 MJ/kg24,936 BTU/lb

Embodied Carbon (primary production)

4.2 kg CO₂/kg
3.9 kg CO₂/kg

Embodied Water

320 L/kg38.3 gal/lb
300 L/kg35.9 gal/lb

Same in both: Typical Recycled Content 40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

59 kN·m/kg
52 kN·m/kg

Specific Stiffness (E / density)

13.1 MN·m/kg
13.4 MN·m/kg

Modulus of Resilience

880 kJ/m³
617 kJ/m³

Thermal Diffusivity

20.2 mm²/s
17.1 mm²/s

Thermal Shock Resistance Index

16
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 scaleC51900C65100

Manufacturing and finishing

CapabilityC51900C65100
CNC machiningYes—
Sheet metalYes—
Default condition——
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.

C51900 vs C65100 — frequently asked

Is C51900 stronger than C65100?

Yes. C51900 has a typical yield strength of 450 MPa (65.3 ksi) against 380 MPa (55.1 ksi) for C65100 — about 18% more. Tensile strength is 520 MPa (75.4 ksi) vs 455 MPa (66 ksi).

Which is cheaper, C51900 or C65100?

C65100 is the lower-cost material: it sits in the high tier ($$$$) while C51900 is specialty ($$$$$). 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, C51900 or C65100?

C65100, by a small margin. Both rate poor for machinability — 30/100 against 25/100 for C51900; for welding the order is C65100 first (excellent, 92/100) then C51900 (fair, 45/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C51900 and C65100 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.