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Steel T13A vs T7A

Steel · grade comparison

Steel T13A and T7A are both steel grades. T13A is the stronger of the two: yield strength 420 MPa (60.9 ksi) against 380 MPa (55.1 ksi) for T7A, about 11% more; tensile strength follows at 700 MPa (102 ksi) vs 660 MPa (95.7 ksi). In exchange, T7A is the more ductile: elongation 22% versus 18% for T13A, and T13A is harder (197 HB vs 180 HB). On the shop floor, T7A machines more easily (good vs fair).

T13AChoose it when strength drives the design.

T7AChoose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

T13A vs T7A: properties

T13AT7A

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
207 GPa30 Msi

Shear Modulus

81 GPa11.7 Msi
80 GPa11.6 Msi

Tensile Strength (Ultimate)

700 MPa102 ksi
660 MPa95.7 ksi

Yield Strength (0.2% offset)

420 MPa60.9 ksi
380 MPa55.1 ksi

Elongation at Break

18%
22%

Reduction in Area

35%
40%

Compressive Strength

480 MPa69.6 ksi
400 MPa58 ksi

Shear Strength

450 MPa65.3 ksi
430 MPa62.4 ksi

Fatigue Strength (Endurance Limit)

320 MPa46.4 ksi
300 MPa43.5 ksi

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

197 HB
180 HB

Hardness, Rockwell B

92 HRB
89 HRB

Hardness, Vickers

207 HV
190 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Density

7.81 g/cm³0.28 lb/in³
7.83 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
1,480°C2,696 °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.

Same in both: Electrical Conductivity 9.5 % IACS · 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
-0.61 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
62 / 100

Machinability Rating (AISI 1212 = 100 %)

30%
65%

Weldability

12 / 100
20 / 100

Formability (cold)

35 / 100
45 / 100

Brazeability / Solderability

50 / 100
55 / 100

Polishability

80 / 100
70 / 100

Castability

—
30 / 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
2.1 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
84 kN·m/kg

Specific Stiffness (E / density)

26.9 MN·m/kg
26.4 MN·m/kg

Modulus of Resilience

420 kJ/m³
349 kJ/m³

Thermal Diffusivity

13.1 mm²/s
13 mm²/s

Thermal Shock Resistance Index

14
13

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 scaleT7AT13A

Manufacturing and finishing

CapabilityT13AT7A
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 T7A — frequently asked

Is T13A stronger than T7A?

Yes. T13A has a typical yield strength of 420 MPa (60.9 ksi) against 380 MPa (55.1 ksi) for T7A — about 11% more. Tensile strength is 700 MPa (102 ksi) vs 660 MPa (95.7 ksi).

Which is cheaper, T13A or T7A?

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 T7A?

T7A. Its machinability rates good (62/100) against fair (40/100) for T13A; for welding the order is T7A first (poor, 20/100) then T13A (not recommended, 12/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in T13A and T7A 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.