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Steel 22MnB4 +QT-28-32HRC vs 22MnB4 +U

Steel · 22MnB4 temper comparison

22MnB4 +QT-28-32HRC and 22MnB4 +U are two conditions of the same steel grade, 22MnB4: +QT-28-32HRC versus +U (hot rolled). The chemistry is identical, so every difference below comes from the condition. 22MnB4 +QT-28-32HRC is the stronger of the two: yield strength 760 MPa (110 ksi) against 390 MPa (56.6 ksi) for 22MnB4 +U, about 95% more; tensile strength follows at 900 MPa (131 ksi) vs 600 MPa (87 ksi). In exchange, 22MnB4 +U is the more ductile: elongation 20% versus 14% for 22MnB4 +QT-28-32HRC, and 22MnB4 +QT-28-32HRC is harder (285 HB vs 180 HB). 22MnB4 +U runs hotter in service (450°C vs 350°C continuous). On the shop floor, 22MnB4 +U machines more easily (good vs fair) and 22MnB4 +U welds better (good vs fair).

22MnB4 +QT-28-32HRCChoose it when strength drives the design.

22MnB4 +UChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

22MnB4 +QT-28-32HRC vs 22MnB4 +U: properties

22MnB4 +QT-28-32HRC22MnB4 +U

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

900 MPa131 ksi
600 MPa87 ksi

Yield Strength (0.2% offset)

760 MPa110 ksi
390 MPa56.6 ksi

Elongation at Break

14%
20%

Shear Strength

540 MPa78.3 ksi
365 MPa52.9 ksi

Fatigue Strength (Endurance Limit)

410 MPa59.5 ksi
270 MPa39.2 ksi

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
45 J33.2 ft·lbf

Hardness, Brinell

285 HB
180 HB

Hardness, Rockwell B

85 HRB
89 HRB

Hardness, Vickers

300 HV
190 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 · Reduction in Area 58% · Compressive Strength 450 MPa65.3 ksi

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)

350°C662 °F
450°C842 °F

Same in both: Thermal Conductivity 44 W/m·K25.4 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 8.6 % IACS · Electrical Resistivity 2×10⁻⁷ Ω·m7.87 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 11 / 100

Manufacturability

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

Machinability

45 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
60%

Weldability

40 / 100
62 / 100

Formability (cold)

28 / 100
60 / 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 40 L/kg4.8 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 scale22MnB4

22MnB4 +QT-28-32HRC vs 22MnB4 +U — frequently asked

Is 22MnB4 +QT-28-32HRC stronger than 22MnB4 +U?

Yes. 22MnB4 +QT-28-32HRC has a typical yield strength of 760 MPa (110 ksi) against 390 MPa (56.6 ksi) for 22MnB4 +U — about 95% more. Tensile strength is 900 MPa (131 ksi) vs 600 MPa (87 ksi).

Which condition does FabDigit quote by default, +QT-28-32HRC or +U?

+AC+C is the default 22MnB4 condition in the FabDigit quote flow (neither +QT-28-32HRC nor +U). 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, 22MnB4 +QT-28-32HRC or 22MnB4 +U?

22MnB4 +U. Its machinability rates good (55/100) against fair (45/100) for 22MnB4 +QT-28-32HRC; for welding the order is 22MnB4 +U first (good, 62/100) then 22MnB4 +QT-28-32HRC (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 22MnB4 +QT-28-32HRC and 22MnB4 +U 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.