Nickel Alloy Inconel 617 vs Inconel 718
Nickel Alloy · grade comparison
Nickel Alloy Inconel 617 and Inconel 718 are both nickel alloy grades. Inconel 718 is the stronger of the two: yield strength 550 MPa (79.8 ksi) against 330 MPa (47.9 ksi) for Inconel 617, about 67% more; tensile strength follows at 965 MPa (140 ksi) vs 760 MPa (110 ksi). In exchange, Inconel 617 is the more ductile: elongation 58% versus 45% for Inconel 718, and Inconel 718 is harder (200 HB vs 173 HB). Inconel 617 is stiffer (211 GPa vs 200 GPa) and Inconel 617 runs hotter in service (1,100°C vs 540°C continuous). On the shop floor, Inconel 718 sits in a lower cost tier (premium, $$$) than Inconel 617 (high, $$$$).
Inconel 617Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.
Inconel 718Choose it when strength drives the design, or when cost is the deciding factor.
Inconel 617 vs Inconel 718: 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
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Charpy V-Notch Impact (RT) 130 J95.9 ft·lbf
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 Resistivity
Same in both: Electrical Conductivity 1.4 % IACS
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 Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Castability
Brazeability / Solderability
Polishability
Same in both: Machinability 18 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Thermal Shock Resistance Index 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.
Manufacturing and finishing
| Capability | Inconel 617 | Inconel 718 |
|---|---|---|
| CNC machining | — | Yes |
| Sheet metal | — | Yes |
| 3D printing | — | Yes |
| Default condition | — | Solution Annealed |
| 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 617 vs Inconel 718 — frequently asked
Is Inconel 718 stronger than Inconel 617?
Yes. Inconel 718 has a typical yield strength of 550 MPa (79.8 ksi) against 330 MPa (47.9 ksi) for Inconel 617 — about 67% more. Tensile strength is 965 MPa (140 ksi) vs 760 MPa (110 ksi).
Which is cheaper, Inconel 617 or Inconel 718?
Inconel 718 is the lower-cost material: it sits in the premium tier ($$$) while Inconel 617 is high ($$$$). 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 617 or Inconel 718?
Inconel 617. Its weldability rates very good (75/100) against very good (70/100) for Inconel 718.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Inconel 617 and Inconel 718 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.