Steel 15B48-N vs 15B48 QT 48-52HRC
Steel · 15B48 temper comparison
15B48-N and 15B48 QT 48-52HRC are two conditions of the same steel grade, 15B48: N (normalized) versus QT 48-52HRC. The chemistry is identical, so every difference below comes from the condition. 15B48 QT 48-52HRC is the stronger of the two: yield strength 1,500 MPa (218 ksi) against 450 MPa (65.3 ksi) for 15B48-N, about 3.3 times as much; tensile strength follows at 1,720 MPa (249 ksi) vs 760 MPa (110 ksi). In exchange, 15B48-N is the more ductile: elongation 18% versus 7% for 15B48 QT 48-52HRC, and 15B48-N is harder (217 HB vs 170 HB). 15B48-N runs hotter in service (425°C vs 175°C continuous).
15B48-NChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.
15B48 QT 48-52HRCChoose it when strength drives the design.
15B48-N vs 15B48 QT 48-52HRC: 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
Shear Strength
Fatigue Strength (Endurance Limit)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Same in both: Elastic (Young's) Modulus 205 GPa29.7 Msi · Shear Modulus 80 GPa11.6 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29
Physical
Density and transition temperatures.
Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,420°C2,588 °F · Liquidus Temperature 1,495°C2,723 °F
Thermal
How each material carries heat and how hot it can run.
Max Service Temperature (continuous)
Same in both: Thermal Conductivity 46 W/m·K26.6 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.7 µm/m·K6.5 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 9.5 % IACS · Electrical Resistivity 1.8×10⁻⁷ Ω·m7.09 µΩ·in
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 10 / 100
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Formability (cold)
Same in both: Weldability 35 / 100 · Brazeability / Solderability 55 / 100 · Polishability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Same in both: Embodied Energy (primary production) 27 MJ/kg11,608 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 45 L/kg5.4 gal/lb · Typical Recycled Content 30%
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.
15B48-N vs 15B48 QT 48-52HRC — frequently asked
Is 15B48 QT 48-52HRC stronger than 15B48-N?
Yes. 15B48 QT 48-52HRC has a typical yield strength of 1,500 MPa (218 ksi) against 450 MPa (65.3 ksi) for 15B48-N — about 3.3 times as much. Tensile strength is 1,720 MPa (249 ksi) vs 760 MPa (110 ksi).
Which condition does FabDigit quote by default, N or QT 48-52HRC?
A is the default 15B48 condition in the FabDigit quote flow (neither N nor QT 48-52HRC). 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, 15B48-N or 15B48 QT 48-52HRC?
15B48 QT 48-52HRC. Its machinability rates good (55/100) against fair (50/100) for 15B48-N.
Ready to make it?
Upload a CAD file and FabDigit prices the part in 15B48-N and 15B48 QT 48-52HRC 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.