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Steel 20MnB-N vs 20MnB-QT200

Steel · 20MnB temper comparison

20MnB-N and 20MnB-QT200 are two conditions of the same steel grade, 20MnB: N (normalized) versus QT200 (quenched 860 °C + tempered 200 °C). The chemistry is identical, so every difference below comes from the condition. 20MnB-QT200 is the stronger of the two: yield strength 950 MPa (138 ksi) against 420 MPa (60.9 ksi) for 20MnB-N, about 126% more; tensile strength follows at 1,150 MPa (167 ksi) vs 640 MPa (92.8 ksi). In exchange, 20MnB-N is the more ductile: elongation 21% versus 12% for 20MnB-QT200, and 20MnB-QT200 is harder (355 HB vs 180 HB). 20MnB-N runs hotter in service (300°C vs 180°C continuous). On the shop floor, 20MnB-N machines more easily (good vs poor) and 20MnB-N welds better (good vs fair).

20MnB-NChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

20MnB-QT200Choose it when strength drives the design.

20MnB-N vs 20MnB-QT200: properties

20MnB-N20MnB-QT200

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

640 MPa92.8 ksi
1,150 MPa167 ksi

Yield Strength (0.2% offset)

420 MPa60.9 ksi
950 MPa138 ksi

Elongation at Break

21%
12%

Reduction in Area

55%
50%

Compressive Strength

420 MPa60.9 ksi
400 MPa58 ksi

Shear Strength

410 MPa59.5 ksi
700 MPa102 ksi

Fatigue Strength (Endurance Limit)

300 MPa43.5 ksi
500 MPa72.5 ksi

Fracture Toughness (K_IC)

92 MPa·√m83.7 ksi·√in
90 MPa·√m81.9 ksi·√in

Charpy V-Notch Impact (RT)

75 J55.3 ft·lbf
65 J47.9 ft·lbf

Hardness, Brinell

180 HB
355 HB

Hardness, Rockwell B

89 HRB
88 HRB

Hardness, Vickers

189 HV
375 HV

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

Physical

Density and transition temperatures.

Same in both: Density 7.85 g/cm³0.28 lb/in³ · Melting Point (Solidus) 1,425°C2,597 °F · Liquidus Temperature 1,500°C2,732 °F

Thermal

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

Max Service Temperature (continuous)

300°C572 °F
180°C356 °F

Same in both: Thermal Conductivity 45 W/m·K26 BTU/hr·ft·°F · Specific Heat Capacity 470 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 -40°C-40 °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) -0.62 V · Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

58 / 100
32 / 100

Machinability Rating (AISI 1212 = 100 %)

60%
30%

Weldability

62 / 100
35 / 100

Formability (cold)

68 / 100
65 / 100

Same in both: Brazeability / Solderability 65 / 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 45 L/kg5.4 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.

2005001,0002,0007.588.5Density (g/cm³)Yield strength (MPa) — log scale20MnB

20MnB-N vs 20MnB-QT200 — frequently asked

Is 20MnB-QT200 stronger than 20MnB-N?

Yes. 20MnB-QT200 has a typical yield strength of 950 MPa (138 ksi) against 420 MPa (60.9 ksi) for 20MnB-N — about 126% more. Tensile strength is 1,150 MPa (167 ksi) vs 640 MPa (92.8 ksi).

Which condition does FabDigit quote by default, N or QT200?

HR is the default 20MnB condition in the FabDigit quote flow (neither N nor QT200). 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, 20MnB-N or 20MnB-QT200?

20MnB-N. Its machinability rates good (58/100) against poor (32/100) for 20MnB-QT200; for welding the order is 20MnB-N first (good, 62/100) then 20MnB-QT200 (fair, 35/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 20MnB-N and 20MnB-QT200 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.