Steel En40B-HR vs En40B Nitrided
Steel · En40B temper comparison
En40B-HR and En40B Nitrided are two conditions of the same steel grade, En40B: HR (hot rolled) versus Nitrided. The chemistry is identical, so every difference below comes from the condition. En40B Nitrided is the stronger of the two: yield strength 745 MPa (108 ksi) against 550 MPa (79.8 ksi) for En40B-HR, about 35% more; tensile strength follows at 930 MPa (135 ksi) vs 850 MPa (123 ksi). In exchange, En40B-HR is the more ductile: elongation 16% versus 14% for En40B Nitrided, and En40B Nitrided is harder (277 HB vs 260 HB). En40B Nitrided runs hotter in service (500°C vs 450°C continuous). On the shop floor, En40B-HR machines more easily (fair vs not recommended) and En40B-HR welds better (poor vs not recommended).
En40B-HRChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.
En40B NitridedChoose it when strength drives the design, or when the part sees heat.
En40B-HR vs En40B Nitrided: 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.
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell C
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Fracture Toughness (K_IC) 80 MPa·√m72.8 ksi·√in
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.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 34 W/m·K19.6 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12 µm/m·K6.7 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -40°C-40 °F
Electrical
Conductivity and insulation.
Same in both: Electrical Conductivity 6.6 % IACS · Electrical Resistivity 2.6×10⁻⁷ Ω·m10.2 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V
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) 20 / 100 · Brazeability / Solderability 40 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 31 MJ/kg13,328 BTU/lb · Embodied Carbon (primary production) 2.2 kg CO₂/kg · Embodied Water 60 L/kg7.2 gal/lb · Typical Recycled Content 25%
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.
En40B-HR vs En40B Nitrided — frequently asked
Is En40B Nitrided stronger than En40B-HR?
Yes. En40B Nitrided has a typical yield strength of 745 MPa (108 ksi) against 550 MPa (79.8 ksi) for En40B-HR — about 35% more. Tensile strength is 930 MPa (135 ksi) vs 850 MPa (123 ksi).
Which condition does FabDigit quote by default, HR or Nitrided?
T is the default En40B condition in the FabDigit quote flow (neither HR nor Nitrided). The other condition is available on request or by drawing note — specify it in the material field or the part notes and the quote is priced for it.
Which is easier to machine, En40B-HR or En40B Nitrided?
En40B-HR. Its machinability rates fair (45/100) against not recommended (5/100) for En40B Nitrided; for welding the order is En40B-HR first (poor, 20/100) then En40B Nitrided (not recommended, 2/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in En40B-HR and En40B Nitrided 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.