Nickel Alloy 718 vs Alloy 333
Nickel Alloy · grade comparison
Nickel Alloy 718 and Alloy 333 are both nickel alloy grades. 718 is the stronger of the two: yield strength 1,170 MPa (170 ksi) against 310 MPa (45 ksi) for Alloy 333, about 3.8 times as much; tensile strength follows at 1,375 MPa (199 ksi) vs 690 MPa (100 ksi). In exchange, Alloy 333 is the more ductile: elongation 50% versus 18% for 718, and 718 is harder (390 HB vs 190 HB). Alloy 333 runs hotter in service (1,100°C vs 650°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 good).
718Choose it when strength drives the design.
Alloy 333Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
718 vs Alloy 333: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all nickel alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all nickel alloy grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Elastic (Young's) Modulus
Shear Modulus
Bulk Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Hardness, Rockwell B
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Typical Recycled Content
Same in both: Embodied Carbon (primary production) 12.5 kg CO₂/kg · Embodied Water 400 L/kg47.9 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 24.9 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.
Manufacturing and finishing
| Capability | 718 | Alloy 333 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 3 finishes: Gold Plating, Plasma Spray, Silver Plating.
718 vs Alloy 333 — frequently asked
Is 718 stronger than Alloy 333?
Yes. 718 has a typical yield strength of 1,170 MPa (170 ksi) against 310 MPa (45 ksi) for Alloy 333 — about 3.8 times as much. Tensile strength is 1,375 MPa (199 ksi) vs 690 MPa (100 ksi).
Which is cheaper, 718 or Alloy 333?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, 718 or Alloy 333?
Alloy 333, by a small margin. Both rate poor for machinability — 25/100 against 15/100 for 718; for welding the order is Alloy 333 first (very good, 78/100) then 718 (good, 65/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in 718 and Alloy 333 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.