Steel NM400 vs NM450
Steel · grade comparison
Steel NM400 and NM450 are both steel grades. NM450 is the stronger of the two: yield strength 1,250 MPa (181 ksi) against 1,050 MPa (152 ksi) for NM400, about 19% more; tensile strength follows at 1,450 MPa (210 ksi) vs 1,250 MPa (181 ksi). In exchange, NM400 is the more ductile: elongation 12% versus 10% for NM450, and NM450 is harder (450 HB vs 400 HB). NM400 conducts electricity better (8 % IACS vs 7 % IACS). On the shop floor, NM400 machines more easily (25 vs 15 out of 100) and NM450 sits in a lower cost tier (budget, $) than NM400 (standard, $$).
NM400Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
NM450Choose it when strength drives the design, or when cost is the deciding factor.
NM400 vs NM450: 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.
Bulk Modulus
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Poisson's Ratio 0.29 · Reduction in Area 40% · Fracture Toughness (K_IC) 70 MPa·√m63.7 ksi·√in · Charpy V-Notch Impact (RT) 45 J33.2 ft·lbf
Physical
Density and transition temperatures.
Melting Point (Solidus)
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Liquidus Temperature 1,500°C2,732 °F
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Latent Heat of Fusion
Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Max Service Temperature (continuous) 250°C482 °F · Min Service Temperature -40°C-40 °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 12 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Polishability
Same in both: Formability (cold) 30 / 100 · Brazeability / Solderability 30 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Water
Typical Recycled Content
Same in both: Embodied Energy (primary production) 30 MJ/kg12,898 BTU/lb · Embodied Carbon (primary production) 2.3 kg CO₂/kg
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
Same in both: Specific Stiffness (E / density) 26.8 MN·m/kg
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 | NM400 | NM450 |
|---|---|---|
| CNC machining | Yes | — |
| Sheet metal | Yes | — |
| Default condition | Q&T | — |
| Relative cost | $$ Standard | $ Budget |
| Min. machined wall | 0.8 mm | — |
| Best machined surface | Ra 1.6 µm | — |
| AlCrN | Yes | — |
| AlTiN | Yes | — |
| Black Oxide | Yes | — |
| CVD Al2O3 | Yes | — |
| CVD TiCN | Yes | — |
| CVD TiN | Yes | — |
| Cerakote | Yes | — |
| Chrome Plating | Yes | — |
| CrN | Yes | — |
| DLC | Yes | — |
| E-Coating | Yes | — |
| HVOF Coating | Yes | — |
| Hot-Dip Galvanizing | Yes | — |
| MoS2 | Yes | — |
| Multilayer CVD | Yes | — |
| Nickel Plating | Yes | — |
| PTFE Coating | Yes | — |
| Painting | Yes | — |
They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.
NM400 vs NM450 — frequently asked
Is NM450 stronger than NM400?
Yes. NM450 has a typical yield strength of 1,250 MPa (181 ksi) against 1,050 MPa (152 ksi) for NM400 — about 19% more. Tensile strength is 1,450 MPa (210 ksi) vs 1,250 MPa (181 ksi).
Which is cheaper, NM400 or NM450?
NM450 is the lower-cost material: it sits in the budget tier ($) while NM400 is standard ($$). 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, NM400 or NM450?
NM400, by a small margin. Both rate poor for machinability — 25/100 against 15/100 for NM450; for welding the order is NM450 first (good, 60/100) then NM400 (good, 55/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in NM400 and NM450 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.