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Stainless Steel E308LT-1 vs ER309LSi

Stainless Steel · grade comparison

Stainless Steel E308LT-1 and ER309LSi are both stainless steel grades. Both yield at about 410 MPa — strength does not separate them. ER309LSi runs hotter in service (950°C vs 800°C continuous). On the shop floor, E308LT-1 forms better (very good vs good) and E308LT-1 sits in a lower cost tier (premium, $$$) than ER309LSi (high, $$$$).

E308LT-1Choose it when cost is the deciding factor.

ER309LSiChoose it when the part sees heat.

E308LT-1 vs ER309LSi: properties

E308LT-1ER309LSi

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

195 GPa28.3 Msi
200 GPa29 Msi

Bulk Modulus

140 GPa20.3 Msi
160 GPa23.2 Msi

Poisson's Ratio

0.29
0.28

Yield Strength (0.2% offset)

410 MPa59.5 ksi
400 MPa58 ksi

Elongation at Break

40%
38%

Reduction in Area

55%
50%

Compressive Strength

410 MPa59.5 ksi
400 MPa58 ksi

Shear Strength

380 MPa55.1 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

225 MPa32.6 ksi
240 MPa34.8 ksi

Fracture Toughness (K_IC)

140 MPa·√m127 ksi·√in
110 MPa·√m100 ksi·√in

Charpy V-Notch Impact (RT)

52 J38.4 ft·lbf
75 J55.3 ft·lbf

Hardness, Brinell

180 HB
185 HB

Hardness, Rockwell B

88 HRB
90 HRB

Hardness, Vickers

190 HV
195 HV

Same in both: Shear Modulus 77 GPa11.2 Msi · Tensile Strength (Ultimate) 590 MPa85.6 ksi

Physical

Density and transition temperatures.

Same in both: Density 7.9 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F · Liquidus Temperature 1,450°C2,642 °F

Thermal

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

Thermal Expansion (CTE, 20–100 °C)

16.6 µm/m·K9.2 µin/in·°F
16 µm/m·K8.9 µin/in·°F

Latent Heat of Fusion

280 J/g120 BTU/lb
285 J/g123 BTU/lb

Max Service Temperature (continuous)

800°C1,472 °F
950°C1,742 °F

Min Service Temperature

-196°C-321 °F
-100°C-148 °F

Same in both: Thermal Conductivity 15 W/m·K8.7 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.3 % IACS
2.2 % IACS

Electrical Resistivity

7.4×10⁻⁷ Ω·m29.1 µΩ·in
7.8×10⁻⁷ Ω·m30.7 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

63 / 100
70 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.1 V

Manufacturability

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

Machinability

36 / 100
35 / 100

Machinability Rating (AISI 1212 = 100 %)

42%
45%

Formability (cold)

70 / 100
55 / 100

Castability

—
60 / 100

Brazeability / Solderability

—
60 / 100

Same in both: Weldability 92 / 100 · Polishability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

62 MJ/kg26,655 BTU/lb
60 MJ/kg25,795 BTU/lb

Embodied Carbon (primary production)

6.3 kg CO₂/kg
5.5 kg CO₂/kg

Embodied Water

130 L/kg15.6 gal/lb
200 L/kg24 gal/lb

Typical Recycled Content

60%
55%

Common Calculations

Ratios derived from the values above.

Specific Stiffness (E / density)

24.7 MN·m/kg
25.3 MN·m/kg

Modulus of Resilience

431 kJ/m³
400 kJ/m³

Same in both: Specific Strength (UTS / density) 75 kN·m/kg · Thermal Diffusivity 3.8 mm²/s · Thermal Shock Resistance Index 3

Strength versus weight

Yield strength against density for every stainless steel grade in the FabDigit library; the compared grades are highlighted. Up and left is stronger for its weight.

3005007001,0001,5002,0007.27.47.67.888.2Density (g/cm³)Yield strength (MPa) — log scaleER309LSiE308LT-1

Manufacturing and finishing

CapabilityE308LT-1ER309LSi
Default condition——
Relative cost$$$ Premium$$$$ High
Min. machined wall——
Best machined surface——

Both take the same 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.

E308LT-1 vs ER309LSi — frequently asked

What is the difference between E308LT-1 and ER309LSi?

Stainless Steel E308LT-1 and ER309LSi are both stainless steel grades. Both yield at about 410 MPa — strength does not separate them. ER309LSi runs hotter in service (950°C vs 800°C continuous).

Which is cheaper, E308LT-1 or ER309LSi?

E308LT-1 is the lower-cost material: it sits in the premium tier ($$$) while ER309LSi is high ($$$$). 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 E308LT-1 over ER309LSi?

Pick E308LT-1 when cost is the deciding factor. Pick ER309LSi when the part sees heat.

Ready to make it?

Upload a CAD file and FabDigit prices the part in E308LT-1 and ER309LSi 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.