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Copper Alloy C68100 vs ERCuSi-A

Copper Alloy · grade comparison

Copper Alloy C68100 and ERCuSi-A are both copper alloy grades. C68100 is the stronger of the two: tensile strength 415 MPa (60.2 ksi) against 350 MPa (50.8 ksi) for ERCuSi-A, about 19% more. In exchange, ERCuSi-A is the more ductile: elongation 38% versus 25% for C68100, and C68100 is harder (105 HB vs 85 HB). C68100 conducts heat better (120 W/m·K vs 36 W/m·K). On the shop floor, C68100 machines more easily (fair vs poor) and ERCuSi-A welds better (excellent vs very good).

C68100Choose it when strength drives the design, or when the part is machined in volume.

ERCuSi-AChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

C68100 vs ERCuSi-A: properties

C68100ERCuSi-A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

100 GPa14.5 Msi
103 GPa14.9 Msi

Shear Modulus

38 GPa5.5 Msi
38.5 GPa5.6 Msi

Bulk Modulus

110 GPa16 Msi
115 GPa16.7 Msi

Poisson's Ratio

0.34
0.35

Tensile Strength (Ultimate)

415 MPa60.2 ksi
350 MPa50.8 ksi

Yield Strength (0.2% offset)

190 MPa27.6 ksi
195 MPa28.3 ksi

Elongation at Break

25%
38%

Reduction in Area

35%
45%

Shear Strength

250 MPa36.3 ksi
215 MPa31.2 ksi

Fatigue Strength (Endurance Limit)

130 MPa18.9 ksi
145 MPa21 ksi

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
60 J44.3 ft·lbf

Hardness, Brinell

105 HB
85 HB

Hardness, Rockwell B

62 HRB
45 HRB

Hardness, Vickers

110 HV
90 HV

Physical

Density and transition temperatures.

Density

8.4 g/cm³0.3 lb/in³
8.53 g/cm³0.31 lb/in³

Melting Point (Solidus)

866°C1,591 °F
970°C1,778 °F

Liquidus Temperature

888°C1,630 °F
1,025°C1,877 °F

Thermal

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

Thermal Conductivity

120 W/m·K69.3 BTU/hr·ft·°F
36 W/m·K20.8 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

21 µm/m·K11.7 µin/in·°F
18 µm/m·K10 µin/in·°F

Latent Heat of Fusion

170 J/g73.1 BTU/lb
205 J/g88.1 BTU/lb

Min Service Temperature

-100°C-148 °F
-196°C-321 °F

Same in both: Specific Heat Capacity 380 J/kg·K0.09 BTU/lb·°F · Max Service Temperature (continuous) 200°C392 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

25 % IACS
7 % IACS

Electrical Resistivity

6.9×10⁻⁸ Ω·m2.72 µΩ·in
2.46×10⁻⁷ Ω·m9.69 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.26 V

Corrosion Resistance

55 / 100
72 / 100

Manufacturability

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

Machinability

45 / 100
33 / 100

Weldability

80 / 100
90 / 100

Formability (cold)

60 / 100
70 / 100

Castability

70 / 100
60 / 100

Brazeability / Solderability

90 / 100
92 / 100

Polishability

70 / 100
75 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 30%

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
57 MJ/kg24,506 BTU/lb

Embodied Carbon (primary production)

3.6 kg CO₂/kg
3.8 kg CO₂/kg

Embodied Water

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

Same in both: Typical Recycled Content 40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

49 kN·m/kg
41 kN·m/kg

Specific Stiffness (E / density)

11.9 MN·m/kg
12.1 MN·m/kg

Modulus of Resilience

181 kJ/m³
185 kJ/m³

Thermal Diffusivity

37.6 mm²/s
11.1 mm²/s

Thermal Shock Resistance Index

24
7

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 scaleERCuSi-AC68100

Manufacturing and finishing

CapabilityC68100ERCuSi-A
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Both take the same 4 finishes: Copper Plating, Electroless Nickel (EN), Gold Plating, Silver Plating.

C68100 vs ERCuSi-A — frequently asked

Is C68100 stronger than ERCuSi-A?

Yes. C68100 has a typical tensile strength of 415 MPa (60.2 ksi) against 350 MPa (50.8 ksi) for ERCuSi-A — about 19% more.

Which is cheaper, C68100 or ERCuSi-A?

Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, C68100 or ERCuSi-A?

C68100. Its machinability rates fair (45/100) against poor (33/100) for ERCuSi-A; for welding the order is ERCuSi-A first (excellent, 90/100) then C68100 (very good, 80/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C68100 and ERCuSi-A 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.