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Nickel Alloy CW-6MC vs CY-40

Nickel Alloy · grade comparison

Nickel Alloy CW-6MC and CY-40 are both nickel alloy grades. CW-6MC is the stronger of the two: yield strength 315 MPa (45.7 ksi) against 245 MPa (35.5 ksi) for CY-40, about 29% more; tensile strength follows at 550 MPa (79.8 ksi) vs 520 MPa (75.4 ksi). CW-6MC is harder — 180 HB against 145 HB for CY-40 — which matters for wear surfaces and threads. CY-40 runs hotter in service (1,000°C vs 900°C continuous) and CY-40 conducts heat better (14.8 W/m·K vs 9.8 W/m·K). On the shop floor, CW-6MC welds better (excellent vs good).

CW-6MCChoose it when strength drives the design, or when surface hardness matters.

CY-40Choose it when the part sees heat.

CW-6MC vs CY-40: properties

CW-6MCCY-40

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

78 GPa11.3 Msi
76 GPa11 Msi

Bulk Modulus

172 GPa24.9 Msi
175 GPa25.4 Msi

Tensile Strength (Ultimate)

550 MPa79.8 ksi
520 MPa75.4 ksi

Yield Strength (0.2% offset)

315 MPa45.7 ksi
245 MPa35.5 ksi

Elongation at Break

40%
38%

Shear Strength

380 MPa55.1 ksi
350 MPa50.8 ksi

Fatigue Strength (Endurance Limit)

260 MPa37.7 ksi
215 MPa31.2 ksi

Fracture Toughness (K_IC)

110 MPa·√m100 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

90 J66.4 ft·lbf
55 J40.6 ft·lbf

Hardness, Brinell

180 HB
145 HB

Hardness, Rockwell B

89 HRB
78 HRB

Compressive Strength

—
250 MPa36.3 ksi

Hardness, Vickers

—
152 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Poisson's Ratio 0.31 · Reduction in Area 40%

Physical

Density and transition temperatures.

Density

8.44 g/cm³0.3 lb/in³
8.45 g/cm³0.31 lb/in³

Melting Point (Solidus)

1,290°C2,354 °F
1,354°C2,469 °F

Liquidus Temperature

1,350°C2,462 °F
1,413°C2,575 °F

Thermal

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

Thermal Conductivity

9.8 W/m·K5.7 BTU/hr·ft·°F
14.8 W/m·K8.6 BTU/hr·ft·°F

Specific Heat Capacity

410 J/kg·K0.1 BTU/lb·°F
444 J/kg·K0.11 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

12.8 µm/m·K7.1 µin/in·°F
13.3 µm/m·K7.4 µin/in·°F

Max Service Temperature (continuous)

900°C1,652 °F
1,000°C1,832 °F

Same in both: Latent Heat of Fusion 290 J/g125 BTU/lb · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

1.3 % IACS
1.7 % IACS

Electrical Resistivity

1.29×10⁻⁶ Ω·m50.8 µΩ·in
1.03×10⁻⁶ Ω·m40.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.15 V
-0.18 V

Corrosion Resistance

90 / 100
76 / 100

Manufacturability

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

Machinability

22 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

14%
15%

Weldability

85 / 100
60 / 100

Castability

65 / 100
58 / 100

Brazeability / Solderability

60 / 100
55 / 100

Polishability

70 / 100
60 / 100

Same in both: Formability (cold) 20 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

155 MJ/kg66,638 BTU/lb
150 MJ/kg64,488 BTU/lb

Embodied Carbon (primary production)

13 kg CO₂/kg
12 kg CO₂/kg

Embodied Water

400 L/kg47.9 gal/lb
350 L/kg41.9 gal/lb

Typical Recycled Content

40%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

65 kN·m/kg
62 kN·m/kg

Modulus of Resilience

248 kJ/m³
150 kJ/m³

Thermal Diffusivity

2.8 mm²/s
3.9 mm²/s

Thermal Shock Resistance Index

2
3

Same in both: Specific Stiffness (E / density) 23.7 MN·m/kg

Strength versus weight

Yield strength against density for every nickel alloy grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

2005001,0006.577.588.59Density (g/cm³)Yield strength (MPa) — log scaleCY-40CW-6MC

Manufacturing and finishing

CapabilityCW-6MCCY-40
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

Both take the same 3 finishes: Gold Plating, Plasma Spray, Silver Plating.

CW-6MC vs CY-40 — frequently asked

Is CW-6MC stronger than CY-40?

Yes. CW-6MC has a typical yield strength of 315 MPa (45.7 ksi) against 245 MPa (35.5 ksi) for CY-40 — about 29% more. Tensile strength is 550 MPa (79.8 ksi) vs 520 MPa (75.4 ksi).

Which is cheaper, CW-6MC or CY-40?

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, CW-6MC or CY-40?

CY-40, by a small margin. Both rate poor for machinability — 28/100 against 22/100 for CW-6MC; for welding the order is CW-6MC first (excellent, 85/100) then CY-40 (good, 60/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in CW-6MC and CY-40 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.