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Steel 9SMnPb28 +A vs 9SMnPb28 +C

Steel · 9SMnPb28 temper comparison

9SMnPb28 +A and 9SMnPb28 +C are two conditions of the same steel grade, 9SMnPb28: +A (annealed) versus +C (cold drawn). The chemistry is identical, so every difference below comes from the condition. 9SMnPb28 +C is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 230 MPa (33.4 ksi) for 9SMnPb28 +A, about 96% more; tensile strength follows at 560 MPa (81.2 ksi) vs 400 MPa (58 ksi). In exchange, 9SMnPb28 +A is the more ductile: elongation 26% versus 9% for 9SMnPb28 +C, and 9SMnPb28 +C is harder (175 HB vs 120 HB). On the shop floor, 9SMnPb28 +C machines more easily (excellent vs very good).

9SMnPb28 +AChoose it when the part is bent, formed or impact-loaded.

9SMnPb28 +CChoose it when strength drives the design, or when the part is machined in volume.

9SMnPb28 +A vs 9SMnPb28 +C: properties

9SMnPb28 +A9SMnPb28 +C

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

400 MPa58 ksi
560 MPa81.2 ksi

Yield Strength (0.2% offset)

230 MPa33.4 ksi
450 MPa65.3 ksi

Elongation at Break

26%
9%

Reduction in Area

50%
35%

Shear Strength

245 MPa35.5 ksi
340 MPa49.3 ksi

Fatigue Strength (Endurance Limit)

175 MPa25.4 ksi
250 MPa36.3 ksi

Charpy V-Notch Impact (RT)

22 J16.2 ft·lbf
8 J5.9 ft·lbf

Hardness, Brinell

120 HB
175 HB

Hardness, Rockwell B

68 HRB
88 HRB

Hardness, Vickers

126 HV
185 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) 1,420°C2,588 °F · Liquidus Temperature 1,510°C2,750 °F

Thermal

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

Thermal Conductivity

52 W/m·K30 BTU/hr·ft·°F
50 W/m·K28.9 BTU/hr·ft·°F

Same in both: Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.5 µm/m·K6.4 µin/in·°F · Latent Heat of Fusion 247 J/g106 BTU/lb · Max Service Temperature (continuous) 250°C482 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

11 % IACS
10.5 % IACS

Electrical Resistivity

1.6×10⁻⁷ Ω·m6.3 µΩ·in
1.65×10⁻⁷ Ω·m6.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Same in both: Galvanic Potential (seawater, vs SCE) -0.61 V · Corrosion Resistance 8 / 100

Manufacturability

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

Machinability

80 / 100
95 / 100

Machinability Rating (AISI 1212 = 100 %)

115%
140%

Weldability

10 / 100
8 / 100

Formability (cold)

50 / 100
20 / 100

Same in both: Brazeability / Solderability 40 / 100 · Polishability 45 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 25 MJ/kg10,748 BTU/lb · Embodied Carbon (primary production) 2 kg CO₂/kg · Embodied Water 40 L/kg4.8 gal/lb · Typical Recycled Content 40%

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 scale9SMnPb28

9SMnPb28 +A vs 9SMnPb28 +C — frequently asked

Is 9SMnPb28 +C stronger than 9SMnPb28 +A?

Yes. 9SMnPb28 +C has a typical yield strength of 450 MPa (65.3 ksi) against 230 MPa (33.4 ksi) for 9SMnPb28 +A — about 96% more. Tensile strength is 560 MPa (81.2 ksi) vs 400 MPa (58 ksi).

Which condition does FabDigit quote by default, +A or +C?

+C is the default 9SMnPb28 condition in the FabDigit quote flow. 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, 9SMnPb28 +A or 9SMnPb28 +C?

9SMnPb28 +C. Its machinability rates excellent (95/100) against very good (80/100) for 9SMnPb28 +A.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 9SMnPb28 +A and 9SMnPb28 +C 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.