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Steel SCMn3-F vs SCMn3-SR

Steel · SCMn3 temper comparison

SCMn3-F and SCMn3-SR are two conditions of the same steel grade, SCMn3: F (as fabricated) versus SR (stress relieved). The chemistry is identical, so every difference below comes from the condition. SCMn3-SR is the stronger of the two: yield strength 420 MPa (60.9 ksi) against 340 MPa (49.3 ksi) for SCMn3-F, about 24% more; tensile strength follows at 680 MPa (98.6 ksi) vs 620 MPa (89.9 ksi). SCMn3-SR is the more ductile: elongation 17% versus 10% for SCMn3-F. SCMn3-SR runs hotter in service (400°C vs 350°C continuous). On the shop floor, SCMn3-SR welds better (50 vs 40 out of 100).

SCMn3-SRChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.

SCMn3-F vs SCMn3-SR: properties

SCMn3-FSCMn3-SR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

620 MPa89.9 ksi
680 MPa98.6 ksi

Yield Strength (0.2% offset)

340 MPa49.3 ksi
420 MPa60.9 ksi

Elongation at Break

10%
17%

Reduction in Area

18%
34%

Compressive Strength

340 MPa49.3 ksi
420 MPa60.9 ksi

Shear Strength

400 MPa58 ksi
445 MPa64.5 ksi

Fatigue Strength (Endurance Limit)

250 MPa36.3 ksi
295 MPa42.8 ksi

Fracture Toughness (K_IC)

55 MPa·√m50.1 ksi·√in
72 MPa·√m65.5 ksi·√in

Charpy V-Notch Impact (RT)

12 J8.9 ft·lbf
28 J20.7 ft·lbf

Hardness, Brinell

195 HB
200 HB

Hardness, Rockwell B

92 HRB
93 HRB

Hardness, Vickers

205 HV
210 HV

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) 1,425°C2,597 °F · Liquidus Temperature 1,490°C2,714 °F

Thermal

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

Max Service Temperature (continuous)

350°C662 °F
400°C752 °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 270 J/g116 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 8 % IACS · Electrical Resistivity 2.1×10⁻⁷ Ω·m8.27 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.6 V · Corrosion Resistance 12 / 100

Manufacturability

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

Machinability

45 / 100
50 / 100

Machinability Rating (AISI 1212 = 100 %)

50%
55%

Weldability

40 / 100
50 / 100

Formability (cold)

10 / 100
15 / 100

Same in both: Castability 70 / 100 · Brazeability / Solderability 55 / 100 · Polishability 50 / 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 60 L/kg7.2 gal/lb · Typical Recycled Content 85%

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 scaleSCMn3

SCMn3-F vs SCMn3-SR — frequently asked

Is SCMn3-SR stronger than SCMn3-F?

Yes. SCMn3-SR has a typical yield strength of 420 MPa (60.9 ksi) against 340 MPa (49.3 ksi) for SCMn3-F — about 24% more. Tensile strength is 680 MPa (98.6 ksi) vs 620 MPa (89.9 ksi).

Which condition does FabDigit quote by default, F or SR?

N+T is the default SCMn3 condition in the FabDigit quote flow (neither F nor SR). 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, SCMn3-F or SCMn3-SR?

SCMn3-SR, by a small margin. Both rate fair for machinability — 50/100 against 45/100 for SCMn3-F; for welding the order is SCMn3-SR first (fair, 50/100) then SCMn3-F (fair, 40/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in SCMn3-F and SCMn3-SR 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.