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Steel T9A-N vs T9A-SR

Steel · T9A temper comparison

T9A-N and T9A-SR are two conditions of the same steel grade, T9A: N (normalized) versus SR (stress relieved). The chemistry is identical, so every difference below comes from the condition. T9A-N is the stronger of the two: yield strength 500 MPa (72.5 ksi) against 420 MPa (60.9 ksi) for T9A-SR, about 19% more; tensile strength follows at 880 MPa (128 ksi) vs 710 MPa (103 ksi). In exchange, T9A-SR is the more ductile: elongation 20% versus 12% for T9A-N, and T9A-N is harder (260 HB vs 195 HB). T9A-SR runs hotter in service (250°C vs 200°C continuous). On the shop floor, T9A-SR machines more easily (good vs fair).

T9A-NChoose it when strength drives the design.

T9A-SRChoose it when the part is bent, formed or impact-loaded, or when the part sees heat.

T9A-N vs T9A-SR: properties

T9A-NT9A-SR

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

880 MPa128 ksi
710 MPa103 ksi

Yield Strength (0.2% offset)

500 MPa72.5 ksi
420 MPa60.9 ksi

Elongation at Break

12%
20%

Reduction in Area

27%
42%

Compressive Strength

515 MPa74.7 ksi
430 MPa62.4 ksi

Shear Strength

530 MPa76.9 ksi
440 MPa63.8 ksi

Fatigue Strength (Endurance Limit)

390 MPa56.6 ksi
320 MPa46.4 ksi

Charpy V-Notch Impact (RT)

10 J7.4 ft·lbf
28 J20.7 ft·lbf

Hardness, Brinell

260 HB
195 HB

Hardness, Rockwell B

101 HRB
92 HRB

Hardness, Vickers

273 HV
205 HV

Same in both: Elastic (Young's) Modulus 210 GPa30.5 Msi · Shear Modulus 81 GPa11.7 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 1,470°C2,678 °F

Thermal

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

Thermal Conductivity

45 W/m·K26 BTU/hr·ft·°F
48 W/m·K27.7 BTU/hr·ft·°F

Max Service Temperature (continuous)

200°C392 °F
250°C482 °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 250 J/g107 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.5 % IACS
9.8 % IACS

Electrical Resistivity

1.82×10⁻⁷ Ω·m7.17 µΩ·in
1.76×10⁻⁷ Ω·m6.93 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

42 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
60%

Weldability

12 / 100
15 / 100

Formability (cold)

20 / 100
38 / 100

Same in both: Castability 20 / 100 · Brazeability / Solderability 45 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Same in both: Embodied Energy (primary production) 26 MJ/kg11,178 BTU/lb · Embodied Carbon (primary production) 2 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 scaleT9A

T9A-N vs T9A-SR — frequently asked

Is T9A-N stronger than T9A-SR?

Yes. T9A-N has a typical yield strength of 500 MPa (72.5 ksi) against 420 MPa (60.9 ksi) for T9A-SR — about 19% more. Tensile strength is 880 MPa (128 ksi) vs 710 MPa (103 ksi).

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

A is the default T9A condition in the FabDigit quote flow (neither N 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, T9A-N or T9A-SR?

T9A-SR. Its machinability rates good (55/100) against fair (42/100) for T9A-N.

Ready to make it?

Upload a CAD file and FabDigit prices the part in T9A-N and T9A-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.