FabDigitFabDigit

Copper Alloy C28000 vs C38000

Copper Alloy · grade comparison

Copper Alloy C28000 and C38000 are both copper alloy grades. C38000 is the stronger of the two: tensile strength 415 MPa (60.2 ksi) against 372 MPa (54 ksi) for C28000, about 12% more. In exchange, C28000 is the more ductile: elongation 45% versus 30% for C38000, and C38000 is harder (100 HB vs 75 HB). C28000 is stiffer (105 GPa vs 97 GPa). On the shop floor, C38000 machines more easily (excellent vs good) and C28000 welds better (fair vs poor).

C28000Choose it when the part is bent, formed or impact-loaded, or when it will be welded.

C38000Choose it when strength drives the design, or when the part is machined in volume.

C28000 vs C38000: properties

C28000C38000

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

105 GPa15.2 Msi
97 GPa14.1 Msi

Shear Modulus

39 GPa5.7 Msi
37 GPa5.4 Msi

Bulk Modulus

112 GPa16.2 Msi
110 GPa16 Msi

Tensile Strength (Ultimate)

372 MPa54 ksi
415 MPa60.2 ksi

Yield Strength (0.2% offset)

145 MPa21 ksi
140 MPa20.3 ksi

Elongation at Break

45%
30%

Shear Strength

255 MPa37 ksi
275 MPa39.9 ksi

Fatigue Strength (Endurance Limit)

138 MPa20 ksi
140 MPa20.3 ksi

Hardness, Brinell

75 HB
100 HB

Hardness, Rockwell B

35 HRB
65 HRB

Charpy V-Notch Impact (RT)

—
25 J18.4 ft·lbf

Hardness, Vickers

—
110 HV

Same in both: Poisson's Ratio 0.34

Physical

Density and transition temperatures.

Density

8.39 g/cm³0.3 lb/in³
8.47 g/cm³0.31 lb/in³

Melting Point (Solidus)

900°C1,652 °F
875°C1,607 °F

Liquidus Temperature

905°C1,661 °F
890°C1,634 °F

Thermal

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

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

20.8 µm/m·K11.6 µin/in·°F
20.9 µm/m·K11.6 µin/in·°F

Latent Heat of Fusion

160 J/g68.8 BTU/lb
165 J/g70.9 BTU/lb

Min Service Temperature

-100°C-148 °F
-200°C-328 °F

Same in both: Thermal Conductivity 123 W/m·K71.1 BTU/hr·ft·°F · Max Service Temperature (continuous) 200°C392 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

28 % IACS
27 % IACS

Electrical Resistivity

6.2×10⁻⁸ Ω·m2.44 µΩ·in
6.4×10⁻⁸ Ω·m2.52 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.28 V
-0.25 V

Same in both: Corrosion Resistance 45 / 100

Manufacturability

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

Machinability

55 / 100
88 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
90%

Weldability

50 / 100
15 / 100

Formability (cold)

55 / 100
25 / 100

Castability

55 / 100
—

Brazeability / Solderability

85 / 100
75 / 100

Polishability

75 / 100
82 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

48 MJ/kg20,636 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

3 kg CO₂/kg
3.5 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

70%
75%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

44 kN·m/kg
49 kN·m/kg

Specific Stiffness (E / density)

12.5 MN·m/kg
11.5 MN·m/kg

Modulus of Resilience

100 kJ/m³
101 kJ/m³

Thermal Diffusivity

39.1 mm²/s
38.2 mm²/s

Thermal Shock Resistance Index

21
25

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 scaleC28000C38000

Manufacturing and finishing

CapabilityC28000C38000
CNC machiningYes—
Sheet metalYes—
Default conditionO—
Relative cost$$$ Premium$$$ Premium
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.

C28000 vs C38000 — frequently asked

Is C38000 stronger than C28000?

Yes. C38000 has a typical tensile strength of 415 MPa (60.2 ksi) against 372 MPa (54 ksi) for C28000 — about 12% more.

Which is cheaper, C28000 or C38000?

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

Which is easier to machine, C28000 or C38000?

C38000. Its machinability rates excellent (88/100) against good (55/100) for C28000; for welding the order is C28000 first (fair, 50/100) then C38000 (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in C28000 and C38000 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.