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Steel M30 vs T8

Steel · grade comparison

Steel M30 and T8 are both steel grades. Both yield at about 590 MPa — strength does not separate them. M30 is lighter (8.03 g/cm³ vs 8.6 g/cm³ for T8) and M30 runs hotter in service (480°C vs 400°C continuous). On the shop floor, T8 sits in a lower cost tier (premium, $$$) than M30 (high, $$$$).

M30Choose it when weight is the constraint, or when the part sees heat.

T8Choose it when cost is the deciding factor.

M30 vs T8: properties

M30T8

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

217 GPa31.5 Msi
220 GPa31.9 Msi

Shear Modulus

83 GPa12 Msi
85 GPa12.3 Msi

Bulk Modulus

160 GPa23.2 Msi
170 GPa24.7 Msi

Poisson's Ratio

0.28
0.29

Yield Strength (0.2% offset)

590 MPa85.6 ksi
570 MPa82.7 ksi

Reduction in Area

28%
25%

Compressive Strength

1,000 MPa145 ksi
1,200 MPa174 ksi

Shear Strength

600 MPa87 ksi
—

Fatigue Strength (Endurance Limit)

420 MPa60.9 ksi
—

Charpy V-Notch Impact (RT)

20 J14.8 ft·lbf
25 J18.4 ft·lbf

Hardness, Brinell

235 HB
240 HB

Hardness, Vickers

247 HV
250 HV

Same in both: Tensile Strength (Ultimate) 900 MPa131 ksi · Elongation at Break 15% · Hardness, Rockwell B 99 HRB

Physical

Density and transition temperatures.

Density

8.03 g/cm³0.29 lb/in³
8.6 g/cm³0.31 lb/in³

Melting Point (Solidus)

1,260°C2,300 °F
1,400°C2,552 °F

Liquidus Temperature

1,425°C2,597 °F
1,460°C2,660 °F

Thermal

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

Thermal Conductivity

24 W/m·K13.9 BTU/hr·ft·°F
22 W/m·K12.7 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10.5 µm/m·K5.8 µin/in·°F
11.2 µm/m·K6.2 µin/in·°F

Max Service Temperature (continuous)

480°C896 °F
400°C752 °F

Min Service Temperature

-50°C-58 °F
-40°C-40 °F

Same in both: Specific Heat Capacity 420 J/kg·K0.1 BTU/lb·°F · Latent Heat of Fusion 250 J/g107 BTU/lb

Electrical

Conductivity and insulation.

Electrical Conductivity

2.9 % IACS
3.1 % IACS

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 µΩ·in
5.5×10⁻⁷ Ω·m21.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.58 V
-0.6 V

Corrosion Resistance

15 / 100
18 / 100

Manufacturability

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

Formability (cold)

15 / 100
12 / 100

Brazeability / Solderability

45 / 100
55 / 100

Polishability

75 / 100
70 / 100

Same in both: Machinability 35 / 100 · Machinability Rating (AISI 1212 = 100 %) 40% · Weldability 15 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

55 MJ/kg23,646 BTU/lb
60 MJ/kg25,795 BTU/lb

Embodied Carbon (primary production)

3.6 kg CO₂/kg
4.2 kg CO₂/kg

Typical Recycled Content

40%
35%

Same in both: Embodied Water 90 L/kg10.8 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

112 kN·m/kg
105 kN·m/kg

Specific Stiffness (E / density)

27 MN·m/kg
25.6 MN·m/kg

Modulus of Resilience

802 kJ/m³
738 kJ/m³

Thermal Diffusivity

7.1 mm²/s
6.1 mm²/s

Thermal Shock Resistance Index

9
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 scaleT8M30

Manufacturing and finishing

CapabilityM30T8
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.

M30 vs T8 — frequently asked

What is the difference between M30 and T8?

Steel M30 and T8 are both steel grades. Both yield at about 590 MPa — strength does not separate them. M30 is lighter (8.03 g/cm³ vs 8.6 g/cm³ for T8) and M30 runs hotter in service (480°C vs 400°C continuous).

Which is cheaper, M30 or T8?

T8 is the lower-cost material: it sits in the premium tier ($$$) while M30 is high ($$$$). 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 M30 over T8?

Pick M30 when weight is the constraint, or when the part sees heat. Pick T8 when cost is the deciding factor.

Ready to make it?

Upload a CAD file and FabDigit prices the part in M30 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.