FabDigitFabDigit

Nickel Alloy Inconel 600 vs Inconel 625

Nickel Alloy · grade comparison

Nickel Alloy Inconel 600 and Inconel 625 are both nickel alloy grades. Inconel 625 is the stronger of the two: yield strength 490 MPa (71.1 ksi) against 255 MPa (37 ksi) for Inconel 600, about 92% more; tensile strength follows at 930 MPa (135 ksi) vs 620 MPa (89.9 ksi). Inconel 625 is harder — 190 HB against 150 HB for Inconel 600 — which matters for wear surfaces and threads. Inconel 600 runs hotter in service (1,100°C vs 650°C continuous) and Inconel 600 conducts heat better (14.9 W/m·K vs 9.8 W/m·K). On the shop floor, Inconel 600 machines more easily (28 vs 18 out of 100) and Inconel 625 sits in a lower cost tier (premium, $$$) than Inconel 600 (high, $$$$).

Inconel 600Choose it when the part sees heat, or when the part is machined in volume.

Inconel 625Choose it when strength drives the design, or when surface hardness matters.

Inconel 600 vs Inconel 625: properties

Inconel 600Inconel 625

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

214 GPa31 Msi
207.5 GPa30.1 Msi

Shear Modulus

76 GPa11 Msi
79 GPa11.5 Msi

Bulk Modulus

200 GPa29 Msi
155 GPa22.5 Msi

Poisson's Ratio

0.32
0.28

Tensile Strength (Ultimate)

620 MPa89.9 ksi
930 MPa135 ksi

Yield Strength (0.2% offset)

255 MPa37 ksi
490 MPa71.1 ksi

Elongation at Break

42%
45%

Reduction in Area

60%
55%

Shear Strength

410 MPa59.5 ksi
600 MPa87 ksi

Fatigue Strength (Endurance Limit)

280 MPa40.6 ksi
420 MPa60.9 ksi

Fracture Toughness (K_IC)

130 MPa·√m118 ksi·√in
110 MPa·√m100 ksi·√in

Charpy V-Notch Impact (RT)

250 J184 ft·lbf
120 J88.5 ft·lbf

Hardness, Brinell

150 HB
190 HB

Hardness, Rockwell B

78 HRB
92 HRB

Compressive Strength

—
500 MPa72.5 ksi

Hardness, Vickers

—
200 HV

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,354°C2,469 °F
1,290°C2,354 °F

Liquidus Temperature

1,413°C2,575 °F
1,350°C2,462 °F

Thermal

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

Thermal Conductivity

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

Specific Heat Capacity

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

Thermal Expansion (CTE, 20–100 °C)

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

Max Service Temperature (continuous)

1,100°C2,012 °F
650°C1,202 °F

Min Service Temperature

-250°C-418 °F
-253°C-423 °F

Same in both: Latent Heat of Fusion 290 J/g125 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

1.7 % IACS
1.3 % IACS

Electrical Resistivity

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

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.17 V
-0.1 V

Corrosion Resistance

78 / 100
90 / 100

Manufacturability

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

Machinability

28 / 100
18 / 100

Machinability Rating (AISI 1212 = 100 %)

25%
12%

Weldability

80 / 100
88 / 100

Formability (cold)

78 / 100
70 / 100

Castability

30 / 100
45 / 100

Polishability

70 / 100
72 / 100

Same in both: Brazeability / Solderability 65 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

150 MJ/kg64,488 BTU/lb
225 MJ/kg96,733 BTU/lb

Embodied Carbon (primary production)

11.5 kg CO₂/kg
14 kg CO₂/kg

Embodied Water

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

Typical Recycled Content

40%
35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

73 kN·m/kg
110 kN·m/kg

Specific Stiffness (E / density)

25.3 MN·m/kg
24.6 MN·m/kg

Modulus of Resilience

152 kJ/m³
579 kJ/m³

Thermal Diffusivity

4 mm²/s
2.8 mm²/s

Same in both: Thermal Shock Resistance Index 3

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 625Inconel 600

Manufacturing and finishing

CapabilityInconel 600Inconel 625
CNC machining—Yes
Sheet metal—Yes
3D printing—Yes
Default condition—O
Relative cost$$$$ High$$$ Premium
Min. machined wall—1.5 mm
Best machined surface—Ra 1.6 µm
Electropolishing—Yes
HVOF Coating—Yes

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

Inconel 600 vs Inconel 625 — frequently asked

Is Inconel 625 stronger than Inconel 600?

Yes. Inconel 625 has a typical yield strength of 490 MPa (71.1 ksi) against 255 MPa (37 ksi) for Inconel 600 — about 92% more. Tensile strength is 930 MPa (135 ksi) vs 620 MPa (89.9 ksi).

Which is cheaper, Inconel 600 or Inconel 625?

Inconel 625 is the lower-cost material: it sits in the premium tier ($$$) while Inconel 600 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, Inconel 600 or Inconel 625?

Inconel 600, by a small margin. Both rate poor for machinability — 28/100 against 18/100 for Inconel 625; for welding the order is Inconel 625 first (excellent, 88/100) then Inconel 600 (very good, 80/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Inconel 600 and Inconel 625 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.