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Steel 50B44-N vs 50B44-QT205

Steel · 50B44 temper comparison

50B44-N and 50B44-QT205 are two conditions of the same steel grade, 50B44: N (normalized) versus QT205 (Q&T 205 °C). The chemistry is identical, so every difference below comes from the condition. 50B44-QT205 is the stronger of the two: yield strength 1,650 MPa (239 ksi) against 520 MPa (75.4 ksi) for 50B44-N, about 3.2 times as much; tensile strength follows at 2,000 MPa (290 ksi) vs 840 MPa (122 ksi). In exchange, 50B44-N is the more ductile: elongation 20% versus 9% for 50B44-QT205, and 50B44-QT205 is harder (560 HB vs 248 HB). 50B44-N runs hotter in service (400°C vs 150°C continuous). On the shop floor, 50B44-N machines more easily (fair vs poor) and 50B44-N welds better (30 vs 15 out of 100).

50B44-NChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

50B44-QT205Choose it when strength drives the design.

50B44-N vs 50B44-QT205: properties

50B44-N50B44-QT205

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

840 MPa122 ksi
2,000 MPa290 ksi

Yield Strength (0.2% offset)

520 MPa75.4 ksi
1,650 MPa239 ksi

Elongation at Break

20%
9%

Reduction in Area

50%
30%

Shear Strength

420 MPa60.9 ksi
1,200 MPa174 ksi

Fatigue Strength (Endurance Limit)

380 MPa55.1 ksi
700 MPa102 ksi

Charpy V-Notch Impact (RT)

24 J17.7 ft·lbf
10 J7.4 ft·lbf

Hardness, Brinell

248 HB
560 HB

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 · Hardness, Rockwell B 90 HRB

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 1,490°C2,714 °F

Thermal

How each material carries heat and how hot it can run.

Max Service Temperature (continuous)

400°C752 °F
150°C302 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 BTU/hr·ft·°F · Specific Heat Capacity 475 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 12.2 µm/m·K6.8 µin/in·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Min Service Temperature -30°C-22 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 8 % IACS · Electrical Resistivity 2.2×10⁻⁷ Ω·m8.66 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 12 / 100

Manufacturability

FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.

Machinability

51 / 100
20 / 100

Machinability Rating (AISI 1212 = 100 %)

55%
20%

Weldability

30 / 100
15 / 100

Formability (cold)

45 / 100
5 / 100

Same in both: Brazeability / Solderability 55 / 100 · Polishability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 1.9 kg CO₂/kg · Embodied Water 50 L/kg6 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale50B44

50B44-N vs 50B44-QT205 — frequently asked

Is 50B44-QT205 stronger than 50B44-N?

Yes. 50B44-QT205 has a typical yield strength of 1,650 MPa (239 ksi) against 520 MPa (75.4 ksi) for 50B44-N — about 3.2 times as much. Tensile strength is 2,000 MPa (290 ksi) vs 840 MPa (122 ksi).

Which condition does FabDigit quote by default, N or QT205?

A is the default 50B44 condition in the FabDigit quote flow (neither N nor QT205). 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, 50B44-N or 50B44-QT205?

50B44-N. Its machinability rates fair (51/100) against poor (20/100) for 50B44-QT205; for welding the order is 50B44-N first (poor, 30/100) then 50B44-QT205 (poor, 15/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 50B44-N and 50B44-QT205 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.