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Steel T5 vs T8

Steel · grade comparison

Steel T5 and T8 are both steel grades. Both yield at about 590 MPa — strength does not separate them. T8 is the more ductile: elongation 15% versus 12% for T5, and T5 is harder (255 HB vs 240 HB). On the shop floor, T8 sits in a lower cost tier (premium, $$$) than T5 (high, $$$$).

T8Choose it when the part is bent, formed or impact-loaded, or when cost is the deciding factor.

T5 vs T8: properties

T5T8

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

214 GPa31 Msi
220 GPa31.9 Msi

Shear Modulus

83 GPa12 Msi
85 GPa12.3 Msi

Bulk Modulus

165 GPa23.9 Msi
170 GPa24.7 Msi

Yield Strength (0.2% offset)

590 MPa85.6 ksi
570 MPa82.7 ksi

Elongation at Break

12%
15%

Reduction in Area

22%
25%

Compressive Strength

700 MPa102 ksi
1,200 MPa174 ksi

Shear Strength

560 MPa81.2 ksi
—

Fatigue Strength (Endurance Limit)

420 MPa60.9 ksi
—

Fracture Toughness (K_IC)

22 MPa·√m20 ksi·√in
—

Charpy V-Notch Impact (RT)

8 J5.9 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

255 HB
240 HB

Hardness, Rockwell B

100 HRB
99 HRB

Hardness, Vickers

268 HV
250 HV

Same in both: Poisson's Ratio 0.29 · Tensile Strength (Ultimate) 900 MPa131 ksi

Physical

Density and transition temperatures.

Density

8.75 g/cm³0.32 lb/in³
8.6 g/cm³0.31 lb/in³

Liquidus Temperature

1,480°C2,696 °F
1,460°C2,660 °F

Same in both: Melting Point (Solidus) 1,400°C2,552 °F

Thermal

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

Thermal Expansion (CTE, 20–100 °C)

11 µm/m·K6.1 µin/in·°F
11.2 µm/m·K6.2 µin/in·°F

Min Service Temperature

-50°C-58 °F
-40°C-40 °F

Same in both: Thermal Conductivity 22 W/m·K12.7 BTU/hr·ft·°F · Specific Heat Capacity 420 J/kg·K0.1 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb · Max Service Temperature (continuous) 400°C752 °F

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 3.1 % IACS · Electrical Resistivity 5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.55 V
-0.6 V

Same in both: Corrosion Resistance 18 / 100

Manufacturability

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

Machinability

32 / 100
35 / 100

Castability

25 / 100
—

Polishability

60 / 100
70 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 40% · Weldability 15 / 100 · Formability (cold) 12 / 100 · Brazeability / Solderability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

100 MJ/kg42,992 BTU/lb
60 MJ/kg25,795 BTU/lb

Embodied Carbon (primary production)

7 kg CO₂/kg
4.2 kg CO₂/kg

Embodied Water

130 L/kg15.6 gal/lb
90 L/kg10.8 gal/lb

Same in both: Typical Recycled Content 35%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

103 kN·m/kg
105 kN·m/kg

Specific Stiffness (E / density)

24.5 MN·m/kg
25.6 MN·m/kg

Modulus of Resilience

813 kJ/m³
738 kJ/m³

Thermal Diffusivity

6 mm²/s
6.1 mm²/s

Same in both: Thermal Shock Resistance Index 8

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 scaleT8T5

Manufacturing and finishing

CapabilityT5T8
CNC machining—Yes
Default condition—Annealed
Relative cost$$$$ High$$$ Premium
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
E-Coating—Yes
HVOF Coating—Yes
Hot-Dip Galvanizing—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes

They share 9 finishes: Copper Plating, Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Manganese Phosphate, Plasma Spray, Silver Plating, Zinc Phosphate.

T5 vs T8 — frequently asked

What is the difference between T5 and T8?

Steel T5 and T8 are both steel grades. Both yield at about 590 MPa — strength does not separate them. T8 is the more ductile: elongation 15% versus 12% for T5, and T5 is harder (255 HB vs 240 HB).

Which is cheaper, T5 or T8?

T8 is the lower-cost material: it sits in the premium tier ($$$) while T5 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

When should I choose T5 over T8?

Pick T8 when the part is bent, formed or impact-loaded, or when cost is the deciding factor.

Ready to make it?

Upload a CAD file and FabDigit prices the part in T5 and T8 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.