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Nickel Alloy Inconel 625 vs Nimonic 90

Nickel Alloy · grade comparison

Nickel Alloy Inconel 625 and Nimonic 90 are both nickel alloy grades. Nimonic 90 is the stronger of the two: yield strength 810 MPa (117 ksi) against 490 MPa (71.1 ksi) for Inconel 625, about 65% more; tensile strength follows at 1,240 MPa (180 ksi) vs 930 MPa (135 ksi). In exchange, Inconel 625 is the more ductile: elongation 45% versus 27% for Nimonic 90, and Nimonic 90 is harder (330 HB vs 190 HB). Nimonic 90 runs hotter in service (920°C vs 650°C continuous) and Nimonic 90 conducts heat better (11.5 W/m·K vs 9.8 W/m·K). On the shop floor, Inconel 625 welds better (excellent vs poor) and Inconel 625 sits in a lower cost tier (premium, $$$) than Nimonic 90 (high, $$$$).

Inconel 625Choose it when the part is bent, formed or impact-loaded, or when it will be welded.

Nimonic 90Choose it when strength drives the design, or when the part sees heat.

Inconel 625 vs Nimonic 90: properties

Inconel 625Nimonic 90

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

207.5 GPa30.1 Msi
213 GPa30.9 Msi

Shear Modulus

79 GPa11.5 Msi
83 GPa12 Msi

Bulk Modulus

155 GPa22.5 Msi
178 GPa25.8 Msi

Poisson's Ratio

0.28
0.31

Tensile Strength (Ultimate)

930 MPa135 ksi
1,240 MPa180 ksi

Yield Strength (0.2% offset)

490 MPa71.1 ksi
810 MPa117 ksi

Elongation at Break

45%
27%

Reduction in Area

55%
32%

Compressive Strength

500 MPa72.5 ksi
830 MPa120 ksi

Shear Strength

600 MPa87 ksi
760 MPa110 ksi

Fatigue Strength (Endurance Limit)

420 MPa60.9 ksi
430 MPa62.4 ksi

Fracture Toughness (K_IC)

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

Charpy V-Notch Impact (RT)

120 J88.5 ft·lbf
35 J25.8 ft·lbf

Hardness, Brinell

190 HB
330 HB

Hardness, Rockwell B

92 HRB
—

Hardness, Vickers

200 HV
350 HV

Hardness, Rockwell C

—
35 HRC

Physical

Density and transition temperatures.

Density

8.44 g/cm³0.3 lb/in³
8.19 g/cm³0.3 lb/in³

Melting Point (Solidus)

1,290°C2,354 °F
1,310°C2,390 °F

Liquidus Temperature

1,350°C2,462 °F
1,370°C2,498 °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
11.5 W/m·K6.6 BTU/hr·ft·°F

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

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

Latent Heat of Fusion

290 J/g125 BTU/lb
—

Max Service Temperature (continuous)

650°C1,202 °F
920°C1,688 °F

Min Service Temperature

-253°C-423 °F
-196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

1.3 % IACS
1.5 % IACS

Electrical Resistivity

1.29×10⁻⁶ Ω·m50.8 µΩ·in
1.18×10⁻⁶ Ω·m46.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.1 V
-0.15 V

Corrosion Resistance

90 / 100
72 / 100

Manufacturability

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

Machinability

18 / 100
14 / 100

Machinability Rating (AISI 1212 = 100 %)

12%
9%

Weldability

88 / 100
25 / 100

Formability (cold)

70 / 100
20 / 100

Castability

45 / 100
35 / 100

Brazeability / Solderability

65 / 100
45 / 100

Polishability

72 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

225 MJ/kg96,733 BTU/lb
240 MJ/kg103,182 BTU/lb

Embodied Carbon (primary production)

14 kg CO₂/kg
16 kg CO₂/kg

Embodied Water

300 L/kg35.9 gal/lb
500 L/kg59.9 gal/lb

Typical Recycled Content

35%
30%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

110 kN·m/kg
151 kN·m/kg

Specific Stiffness (E / density)

24.6 MN·m/kg
26 MN·m/kg

Modulus of Resilience

579 kJ/m³
1,540 kJ/m³

Thermal Diffusivity

2.8 mm²/s
3 mm²/s

Thermal Shock Resistance Index

3
5

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 scaleInconel 625Nimonic 90

Manufacturing and finishing

CapabilityInconel 625Nimonic 90
CNC machiningYes—
Sheet metalYes—
3D printingYes—
Default conditionO—
Relative cost$$$ Premium$$$$ High
Min. machined wall1.5 mm—
Best machined surfaceRa 1.6 µm—
ElectropolishingYes—
HVOF CoatingYes—

They share 3 finishes: Gold Plating, Plasma Spray, Silver Plating.

Inconel 625 vs Nimonic 90 — frequently asked

Is Nimonic 90 stronger than Inconel 625?

Yes. Nimonic 90 has a typical yield strength of 810 MPa (117 ksi) against 490 MPa (71.1 ksi) for Inconel 625 — about 65% more. Tensile strength is 1,240 MPa (180 ksi) vs 930 MPa (135 ksi).

Which is cheaper, Inconel 625 or Nimonic 90?

Inconel 625 is the lower-cost material: it sits in the premium tier ($$$) while Nimonic 90 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, Inconel 625 or Nimonic 90?

Inconel 625. Its weldability rates excellent (88/100) against poor (25/100) for Nimonic 90.

Ready to make it?

Upload a CAD file and FabDigit prices the part in Inconel 625 and Nimonic 90 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.