Nickel Alloy Alloy 30 vs Alloy 686
Nickel Alloy · grade comparison
Nickel Alloy Alloy 30 and Alloy 686 are both nickel alloy grades. Alloy 686 is the stronger of the two: yield strength 380 MPa (55.1 ksi) against 320 MPa (46.4 ksi) for Alloy 30, about 19% more; tensile strength follows at 760 MPa (110 ksi) vs 690 MPa (100 ksi). Alloy 686 is harder — 190 HB against 170 HB for Alloy 30 — which matters for wear surfaces and threads. Alloy 30 is lighter (8.22 g/cm³ vs 8.73 g/cm³ for Alloy 686) and Alloy 686 runs hotter in service (1,000°C vs 675°C continuous).
Alloy 30Choose it when weight is the constraint.
Alloy 686Choose it when strength drives the design, or when surface hardness matters.
Alloy 30 vs Alloy 686: 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
Compressive Strength
Hardness, Vickers
Same in both: Fatigue Strength (Endurance Limit) 300 MPa43.5 ksi
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)
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.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.12 V
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Formability (cold)
Castability
Polishability
Same in both: Machinability Rating (AISI 1212 = 100 %) 12% · Weldability 80 / 100 · Brazeability / Solderability 55 / 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 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.
Manufacturing and finishing
| Capability | Alloy 30 | Alloy 686 |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 3 finishes: Gold Plating, Plasma Spray, Silver Plating.
Alloy 30 vs Alloy 686 — frequently asked
Is Alloy 686 stronger than Alloy 30?
Yes. Alloy 686 has a typical yield strength of 380 MPa (55.1 ksi) against 320 MPa (46.4 ksi) for Alloy 30 — about 19% more. Tensile strength is 760 MPa (110 ksi) vs 690 MPa (100 ksi).
Which is cheaper, Alloy 30 or Alloy 686?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
Which is easier to machine, Alloy 30 or Alloy 686?
Alloy 30, by a small margin. Both rate poor for machinability — 25/100 against 18/100 for Alloy 686.
Ready to make it?
Upload a CAD file and FabDigit prices the part in Alloy 30 and Alloy 686 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.