Steel NAK55 vs P20
Steel · grade comparison
Steel NAK55 and P20 are both steel grades, both mold steel. NAK55 is the stronger of the two: yield strength 560 MPa (81.2 ksi) against 440 MPa (63.8 ksi) for P20, about 27% more; tensile strength follows at 800 MPa (116 ksi) vs 700 MPa (102 ksi). NAK55 is harder — 245 HB against 200 HB for P20 — which matters for wear surfaces and threads. NAK55 conducts heat better (39 W/m·K vs 32 W/m·K). On the shop floor, P20 welds better (50 vs 40 out of 100) and NAK55 sits in a lower cost tier (standard, $$) than P20 (specialty, $$$$$).
NAK55Choose it when strength drives the design, or when surface hardness matters.
P20Choose it when it will be welded.
NAK55 vs P20: 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.
Elastic (Young's) Modulus
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
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
Same in both: Shear Modulus 80 GPa11.6 Msi · Poisson's Ratio 0.29 · Elongation at Break 20%
Physical
Density and transition temperatures.
Same in both: Density 7.8 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,480°C2,696 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Max Service Temperature (continuous)
Latent Heat of Fusion
Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.4 µm/m·K6.9 µin/in·°F · Min Service Temperature -20°C-4 °F
Electrical
Conductivity and insulation.
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Galvanic Potential (seawater, vs SCE)
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Brazeability / Solderability
Polishability
Same in both: Formability (cold) 30 / 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
Thermal Shock Resistance Index
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 | NAK55 | P20 |
|---|---|---|
| Default condition | Annealed | Annealed |
| Relative cost | $$ Standard | $$$$$ Specialty |
| Min. machined wall | 0.8 mm | 0.8 mm |
| Best machined surface | Ra 1.6 µm | Ra 1.6 µm |
Both are offered for CNC machining. Both take the same 38 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, Copper Plating, CrN, DLC, E-Coating and 26 more.
NAK55 vs P20 — frequently asked
Is NAK55 stronger than P20?
Yes. NAK55 has a typical yield strength of 560 MPa (81.2 ksi) against 440 MPa (63.8 ksi) for P20 — about 27% more. Tensile strength is 800 MPa (116 ksi) vs 700 MPa (102 ksi).
Which is cheaper, NAK55 or P20?
NAK55 is the lower-cost material: it sits in the standard tier ($$) while P20 is specialty ($$$$$). 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, NAK55 or P20?
NAK55. Its machinability rates very good (70/100) against good (65/100) for P20; for welding the order is P20 first (fair, 50/100) then NAK55 (fair, 40/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in NAK55 and P20 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.