Nickel Alloy Hastelloy G-3 vs Hastelloy X
Nickel Alloy · grade comparison
Nickel Alloy Hastelloy G-3 and Hastelloy X are both nickel alloy grades. Hastelloy X is the stronger of the two: yield strength 360 MPa (52.2 ksi) against 310 MPa (45 ksi) for Hastelloy G-3, about 16% more; tensile strength follows at 755 MPa (110 ksi) vs 690 MPa (100 ksi). In exchange, Hastelloy G-3 is the more ductile: elongation 50% versus 43% for Hastelloy X, and Hastelloy X is harder (195 HB vs 185 HB). Hastelloy X runs hotter in service (1,150°C vs 650°C continuous) and Hastelloy G-3 conducts heat better (10.2 W/m·K vs 9.1 W/m·K). On the shop floor, Hastelloy X sits in a lower cost tier (premium, $$$) than Hastelloy G-3 (high, $$$$).
Hastelloy G-3Choose it when the part is bent, formed or impact-loaded.
Hastelloy XChoose it when strength drives the design, or when the part sees heat.
Hastelloy G-3 vs Hastelloy X: 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
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Compressive Strength
Fracture Toughness (K_IC)
Same in both: Fatigue Strength (Endurance Limit) 300 MPa43.5 ksi
Physical
Density and transition temperatures.
Density
Same in both: Melting Point (Solidus) 1,260°C2,300 °F · Liquidus Temperature 1,355°C2,471 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Max Service Temperature (continuous)
Same in both: Latent Heat of Fusion 290 J/g125 BTU/lb · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 1.5 % IACS · Electrical Resistivity 1.18×10⁻⁶ Ω·m46.5 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.1 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Brazeability / Solderability
Polishability
Castability
Same in both: Weldability 85 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 35%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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 | Hastelloy G-3 | Hastelloy X |
|---|---|---|
| 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.
Hastelloy G-3 vs Hastelloy X — frequently asked
Is Hastelloy X stronger than Hastelloy G-3?
Yes. Hastelloy X has a typical yield strength of 360 MPa (52.2 ksi) against 310 MPa (45 ksi) for Hastelloy G-3 — about 16% more. Tensile strength is 755 MPa (110 ksi) vs 690 MPa (100 ksi).
Which is cheaper, Hastelloy G-3 or Hastelloy X?
Hastelloy X is the lower-cost material: it sits in the premium tier ($$$) while Hastelloy G-3 is high ($$$$). 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, Hastelloy G-3 or Hastelloy X?
Hastelloy G-3, by a small margin. Both rate poor for machinability — 25/100 against 18/100 for Hastelloy X.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Hastelloy G-3 and Hastelloy X 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.