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Steel T13A vs T9A

Steel · grade comparison

Steel T13A and T9A are both steel grades. Both yield at about 420 MPa — strength does not separate them. T9A is the more ductile: elongation 22% versus 18% for T13A. On the shop floor, T9A machines more easily (good vs fair).

T9AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

T13A vs T9A: properties

T13AT9A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Yield Strength (0.2% offset)

420 MPa60.9 ksi
410 MPa59.5 ksi

Elongation at Break

18%
22%

Reduction in Area

35%
40%

Compressive Strength

480 MPa69.6 ksi
420 MPa60.9 ksi

Shear Strength

450 MPa65.3 ksi
430 MPa62.4 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
310 MPa45 ksi

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

197 HB
190 HB

Hardness, Rockwell B

92 HRB
91 HRB

Hardness, Vickers

207 HV
200 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 · Tensile Strength (Ultimate) 700 MPa102 ksi

Physical

Density and transition temperatures.

Density

7.81 g/cm³0.28 lb/in³
7.85 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,260°C2,300 °F
1,420°C2,588 °F

Liquidus Temperature

1,440°C2,624 °F
1,470°C2,678 °F

Thermal

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

Thermal Expansion (CTE, 20–100 °C)

11.3 µm/m·K6.3 µin/in·°F
11.5 µm/m·K6.4 µin/in·°F

Same in both: Thermal Conductivity 48 W/m·K27.7 BTU/hr·ft·°F · Specific Heat Capacity 470 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 300°C572 °F · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

9.5 % IACS
9.6 % IACS

Same in both: Electrical Resistivity 1.8×10⁻⁷ Ω·m7.09 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.6 V
-0.62 V

Same in both: Corrosion Resistance 10 / 100

Manufacturability

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

Machinability

40 / 100
55 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
60%

Weldability

12 / 100
15 / 100

Formability (cold)

35 / 100
40 / 100

Brazeability / Solderability

50 / 100
45 / 100

Polishability

80 / 100
70 / 100

Castability

—
20 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

30 MJ/kg12,898 BTU/lb
26 MJ/kg11,178 BTU/lb

Embodied Carbon (primary production)

2.3 kg CO₂/kg
2 kg CO₂/kg

Embodied Water

60 L/kg7.2 gal/lb
45 L/kg5.4 gal/lb

Typical Recycled Content

30%
25%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

90 kN·m/kg
89 kN·m/kg

Specific Stiffness (E / density)

26.9 MN·m/kg
26.8 MN·m/kg

Modulus of Resilience

420 kJ/m³
400 kJ/m³

Thermal Diffusivity

13.1 mm²/s
13 mm²/s

Same in both: Thermal Shock Resistance Index 14

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 scaleT9AT13A

Manufacturing and finishing

CapabilityT13AT9A
Default condition——
Relative cost$ Budget$ Budget
Min. machined wall——
Best machined surface——

Both take the same 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

T13A vs T9A — frequently asked

What is the difference between T13A and T9A?

Steel T13A and T9A are both steel grades. Both yield at about 420 MPa — strength does not separate them. T9A is the more ductile: elongation 22% versus 18% for T13A.

Which is cheaper, T13A or T9A?

Both sit in the same relative cost tier ($, budget); the part price will be decided by machining time, tolerance and quantity rather than by the material.

Which is easier to machine, T13A or T9A?

T9A. Its machinability rates good (55/100) against fair (40/100) for T13A.

Ready to make it?

Upload a CAD file and FabDigit prices the part in T13A and T9A 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.