Steel 4-79 Mo-Permalloy vs Supermalloy
Steel · grade comparison
Steel 4-79 Mo-Permalloy and Supermalloy are both steel grades. 4-79 Mo-Permalloy is the stronger of the two: yield strength 260 MPa (37.7 ksi) against 230 MPa (33.4 ksi) for Supermalloy, about 13% more. 4-79 Mo-Permalloy is harder — 130 HV against 120 HV for Supermalloy — which matters for wear surfaces and threads.
4-79 Mo-PermalloyChoose it when strength drives the design, or when surface hardness matters.
4-79 Mo-Permalloy vs Supermalloy: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all steel 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 steel 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.
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Shear Strength
Charpy V-Notch Impact (RT)
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 175 GPa25.4 Msi · Elongation at Break 40% · Reduction in Area 70% · Fatigue Strength (Endurance Limit) 250 MPa36.3 ksi
Physical
Density and transition temperatures.
Density
Same in both: Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F
Thermal
How each material carries heat and how hot it can run.
Latent Heat of Fusion
Same in both: Thermal Conductivity 19 W/m·K11 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.5 µm/m·K6.9 µin/in·°F · Max Service Temperature (continuous) 400°C752 °F · Min Service Temperature -196°C-321 °F
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Same in both: Corrosion Resistance 45 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Brazeability / Solderability
Same in both: Weldability 60 / 100 · Formability (cold) 85 / 100 · Castability 40 / 100 · Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Typical Recycled Content
Same in both: Embodied Water 200 L/kg24 gal/lb
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Same in both: Thermal Diffusivity 4.7 mm²/s · Thermal Shock Resistance Index 4
Strength versus weight
Yield strength against density for every steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.
Manufacturing and finishing
| Capability | 4-79 Mo-Permalloy | Supermalloy |
|---|---|---|
| Default condition | — | — |
| Relative cost | $$$$ High | $$$$ High |
| Min. machined wall | — | — |
| Best machined surface | — | — |
Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
4-79 Mo-Permalloy vs Supermalloy — frequently asked
Is 4-79 Mo-Permalloy stronger than Supermalloy?
Yes. 4-79 Mo-Permalloy has a typical yield strength of 260 MPa (37.7 ksi) against 230 MPa (33.4 ksi) for Supermalloy — about 13% more. Tensile strength is 550 MPa (79.8 ksi) vs 560 MPa (81.2 ksi).
Which is cheaper, 4-79 Mo-Permalloy or Supermalloy?
Both sit in the same relative cost tier ($$$$, high); the part price will be decided by machining time, tolerance and quantity rather than by the material.
When should I choose 4-79 Mo-Permalloy over Supermalloy?
Pick 4-79 Mo-Permalloy when strength drives the design, or when surface hardness matters.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 4-79 Mo-Permalloy and Supermalloy 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.