FabDigitFabDigit

Nickel Alloy Alloy 333 vs Inconel X-750

Nickel Alloy · grade comparison

Nickel Alloy Alloy 333 and Inconel X-750 are both nickel alloy grades. Inconel X-750 is the stronger of the two: yield strength 815 MPa (118 ksi) against 310 MPa (45 ksi) for Alloy 333, about 163% more; tensile strength follows at 1,200 MPa (174 ksi) vs 690 MPa (100 ksi). In exchange, Alloy 333 is the more ductile: elongation 50% versus 25% for Inconel X-750, and Inconel X-750 is harder (302 HB vs 190 HB). Inconel X-750 is stiffer (214 GPa vs 203 GPa) and Alloy 333 runs hotter in service (1,100°C vs 704°C continuous). On the shop floor, Alloy 333 machines more easily (25 vs 15 out of 100) and Alloy 333 welds better (very good vs fair).

Alloy 333Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

Inconel X-750Choose it when strength drives the design.

Alloy 333 vs Inconel X-750: properties

Alloy 333Inconel X-750

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

203 GPa29.4 Msi
214 GPa31 Msi

Shear Modulus

78 GPa11.3 Msi
83 GPa12 Msi

Bulk Modulus

165 GPa23.9 Msi
170 GPa24.7 Msi

Poisson's Ratio

0.31
0.29

Tensile Strength (Ultimate)

690 MPa100 ksi
1,200 MPa174 ksi

Yield Strength (0.2% offset)

310 MPa45 ksi
815 MPa118 ksi

Elongation at Break

50%
25%

Reduction in Area

55%
32%

Compressive Strength

320 MPa46.4 ksi
850 MPa123 ksi

Shear Strength

450 MPa65.3 ksi
730 MPa106 ksi

Fatigue Strength (Endurance Limit)

290 MPa42.1 ksi
480 MPa69.6 ksi

Fracture Toughness (K_IC)

110 MPa·√m100 ksi·√in
100 MPa·√m91 ksi·√in

Charpy V-Notch Impact (RT)

150 J111 ft·lbf
50 J36.9 ft·lbf

Hardness, Brinell

190 HB
302 HB

Hardness, Rockwell B

90 HRB
—

Hardness, Rockwell C

10 HRC
32 HRC

Hardness, Vickers

200 HV
320 HV

Physical

Density and transition temperatures.

Density

8.14 g/cm³0.29 lb/in³
8.28 g/cm³0.3 lb/in³

Melting Point (Solidus)

1,330°C2,426 °F
1,393°C2,539 °F

Liquidus Temperature

1,400°C2,552 °F
1,427°C2,601 °F

Thermal

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

Thermal Conductivity

11 W/m·K6.4 BTU/hr·ft·°F
12 W/m·K6.9 BTU/hr·ft·°F

Specific Heat Capacity

460 J/kg·K0.11 BTU/lb·°F
431 J/kg·K0.1 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

13.9 µm/m·K7.7 µin/in·°F
12.6 µm/m·K7 µin/in·°F

Latent Heat of Fusion

285 J/g123 BTU/lb
290 J/g125 BTU/lb

Max Service Temperature (continuous)

1,100°C2,012 °F
704°C1,299 °F

Min Service Temperature

-196°C-321 °F
-253°C-423 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

1.5 % IACS
1.4 % IACS

Electrical Resistivity

1.16×10⁻⁶ Ω·m45.7 µΩ·in
1.22×10⁻⁶ Ω·m48 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.15 V
-0.05 V

Corrosion Resistance

72 / 100
80 / 100

Manufacturability

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

Machinability

25 / 100
15 / 100

Weldability

78 / 100
40 / 100

Formability (cold)

70 / 100
30 / 100

Castability

40 / 100
30 / 100

Brazeability / Solderability

65 / 100
50 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 12% · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

165 MJ/kg70,937 BTU/lb
190 MJ/kg81,685 BTU/lb

Embodied Carbon (primary production)

12.5 kg CO₂/kg
13 kg CO₂/kg

Embodied Water

400 L/kg47.9 gal/lb
800 L/kg95.9 gal/lb

Same in both: Typical Recycled Content 35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

85 kN·m/kg
145 kN·m/kg

Specific Stiffness (E / density)

24.9 MN·m/kg
25.8 MN·m/kg

Modulus of Resilience

237 kJ/m³
1,552 kJ/m³

Thermal Diffusivity

2.9 mm²/s
3.4 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 scaleAlloy 333Inconel X-750

Manufacturing and finishing

CapabilityAlloy 333Inconel X-750
Default condition——
Relative cost$$$$ High$$$$ High
Min. machined wall——
Best machined surface——

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

Alloy 333 vs Inconel X-750 — frequently asked

Is Inconel X-750 stronger than Alloy 333?

Yes. Inconel X-750 has a typical yield strength of 815 MPa (118 ksi) against 310 MPa (45 ksi) for Alloy 333 — about 163% more. Tensile strength is 1,200 MPa (174 ksi) vs 690 MPa (100 ksi).

Which is cheaper, Alloy 333 or Inconel X-750?

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, Alloy 333 or Inconel X-750?

Alloy 333, by a small margin. Both rate poor for machinability — 25/100 against 15/100 for Inconel X-750; for welding the order is Alloy 333 first (very good, 78/100) then Inconel X-750 (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in Alloy 333 and Inconel X-750 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.