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Nickel Alloy CY-40 vs IN-718 Cast

Nickel Alloy · grade comparison

Nickel Alloy CY-40 and IN-718 Cast are both nickel alloy grades. IN-718 Cast is the stronger of the two: yield strength 862 MPa (125 ksi) against 245 MPa (35.5 ksi) for CY-40, about 3.5 times as much; tensile strength follows at 1,000 MPa (145 ksi) vs 520 MPa (75.4 ksi). In exchange, CY-40 is the more ductile: elongation 38% versus 7% for IN-718 Cast, and IN-718 Cast is harder (352 HB vs 145 HB). IN-718 Cast is lighter (8.19 g/cm³ vs 8.45 g/cm³ for CY-40) and CY-40 runs hotter in service (1,000°C vs 650°C continuous). On the shop floor, CY-40 machines more easily (28 vs 15 out of 100).

CY-40Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

IN-718 CastChoose it when strength drives the design, or when weight is the constraint.

CY-40 vs IN-718 Cast: properties

CY-40IN-718 Cast

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
197 GPa28.6 Msi

Bulk Modulus

175 GPa25.4 Msi
158 GPa22.9 Msi

Poisson's Ratio

0.31
0.29

Tensile Strength (Ultimate)

520 MPa75.4 ksi
1,000 MPa145 ksi

Yield Strength (0.2% offset)

245 MPa35.5 ksi
862 MPa125 ksi

Elongation at Break

38%
7%

Reduction in Area

40%
11%

Compressive Strength

250 MPa36.3 ksi
880 MPa128 ksi

Shear Strength

350 MPa50.8 ksi
650 MPa94.3 ksi

Fatigue Strength (Endurance Limit)

215 MPa31.2 ksi
340 MPa49.3 ksi

Fracture Toughness (K_IC)

90 MPa·√m81.9 ksi·√in
70 MPa·√m63.7 ksi·√in

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
22 J16.2 ft·lbf

Hardness, Brinell

145 HB
352 HB

Hardness, Rockwell B

78 HRB
—

Hardness, Vickers

152 HV
375 HV

Hardness, Rockwell C

—
38 HRC

Same in both: Shear Modulus 76 GPa11 Msi

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,354°C2,469 °F
1,260°C2,300 °F

Liquidus Temperature

1,413°C2,575 °F
1,336°C2,437 °F

Thermal

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

Thermal Conductivity

14.8 W/m·K8.6 BTU/hr·ft·°F
11.4 W/m·K6.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

13.3 µm/m·K7.4 µin/in·°F
13 µm/m·K7.2 µin/in·°F

Latent Heat of Fusion

290 J/g125 BTU/lb
225 J/g96.7 BTU/lb

Max Service Temperature (continuous)

1,000°C1,832 °F
650°C1,202 °F

Min Service Temperature

-196°C-321 °F
-253°C-423 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

1.7 % IACS
1.4 % IACS

Electrical Resistivity

1.03×10⁻⁶ Ω·m40.6 µΩ·in
1.25×10⁻⁶ Ω·m49.2 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.18 V
-0.1 V

Same in both: Corrosion Resistance 76 / 100

Manufacturability

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

Machinability

28 / 100
15 / 100

Machinability Rating (AISI 1212 = 100 %)

15%
12%

Weldability

60 / 100
62 / 100

Formability (cold)

20 / 100
8 / 100

Castability

58 / 100
68 / 100

Polishability

60 / 100
70 / 100

Same in both: Brazeability / Solderability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

150 MJ/kg64,488 BTU/lb
215 MJ/kg92,433 BTU/lb

Embodied Carbon (primary production)

12 kg CO₂/kg
14.5 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

45%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

62 kN·m/kg
122 kN·m/kg

Specific Stiffness (E / density)

23.7 MN·m/kg
24.1 MN·m/kg

Modulus of Resilience

150 kJ/m³
1,886 kJ/m³

Thermal Diffusivity

3.9 mm²/s
3.2 mm²/s

Thermal Shock Resistance Index

3
4

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-40IN-718 Cast

Manufacturing and finishing

CapabilityCY-40IN-718 Cast
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

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

CY-40 vs IN-718 Cast — frequently asked

Is IN-718 Cast stronger than CY-40?

Yes. IN-718 Cast has a typical yield strength of 862 MPa (125 ksi) against 245 MPa (35.5 ksi) for CY-40 — about 3.5 times as much. Tensile strength is 1,000 MPa (145 ksi) vs 520 MPa (75.4 ksi).

Which is cheaper, CY-40 or IN-718 Cast?

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, CY-40 or IN-718 Cast?

CY-40, by a small margin. Both rate poor for machinability — 28/100 against 15/100 for IN-718 Cast.

Ready to make it?

Upload a CAD file and FabDigit prices the part in CY-40 and IN-718 Cast 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.