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Stainless Steel E308L vs ER308Si

Stainless Steel · grade comparison

Stainless Steel E308L and ER308Si are both stainless steel grades. ER308Si is the stronger of the two: tensile strength 600 MPa (87 ksi) against 570 MPa (82.7 ksi) for E308L, about 5% more.

ER308SiChoose it when strength drives the design.

E308L vs ER308Si: properties

E308LER308Si

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Bulk Modulus

140 GPa20.3 Msi
160 GPa23.2 Msi

Tensile Strength (Ultimate)

570 MPa82.7 ksi
600 MPa87 ksi

Elongation at Break

42%
38%

Shear Strength

380 MPa55.1 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
240 MPa34.8 ksi

Fracture Toughness (K_IC)

150 MPa·√m137 ksi·√in
140 MPa·√m127 ksi·√in

Charpy V-Notch Impact (RT)

75 J55.3 ft·lbf
90 J66.4 ft·lbf

Same in both: Elastic (Young's) Modulus 195 GPa28.3 Msi · Shear Modulus 77 GPa11.2 Msi · Poisson's Ratio 0.29 · Yield Strength (0.2% offset) 400 MPa58 ksi · Reduction in Area 55% · Compressive Strength 400 MPa58 ksi · Hardness, Brinell 175 HB · Hardness, Rockwell B 88 HRB · Hardness, Vickers 185 HV

Physical

Density and transition temperatures.

Density

7.9 g/cm³0.29 lb/in³
7.95 g/cm³0.29 lb/in³

Same in both: 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.

Latent Heat of Fusion

285 J/g123 BTU/lb
270 J/g116 BTU/lb

Max Service Temperature (continuous)

700°C1,292 °F
760°C1,400 °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 · Thermal Expansion (CTE, 20–100 °C) 16.5 µm/m·K9.2 µin/in·°F · Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.3 % IACS
2.4 % IACS

Electrical Resistivity

7.4×10⁻⁷ Ω·m29.1 µΩ·in
7.2×10⁻⁷ Ω·m28.3 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.05 V
-0.08 V

Corrosion Resistance

62 / 100
68 / 100

Manufacturability

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

Machinability

38 / 100
40 / 100

Formability (cold)

55 / 100
60 / 100

Same in both: Machinability Rating (AISI 1212 = 100 %) 45% · Weldability 95 / 100 · Brazeability / Solderability 60 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

58 MJ/kg24,936 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Water

120 L/kg14.4 gal/lb
200 L/kg24 gal/lb

Same in both: Embodied Carbon (primary production) 5.5 kg CO₂/kg · Typical Recycled Content 55%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

72 kN·m/kg
75 kN·m/kg

Specific Stiffness (E / density)

24.7 MN·m/kg
24.5 MN·m/kg

Same in both: Modulus of Resilience 410 kJ/m³ · 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 scaleER308SiE308L

Manufacturing and finishing

CapabilityE308LER308Si
Default condition——
Relative cost$$$ Premium$$$ Premium
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.

E308L vs ER308Si — frequently asked

Is ER308Si stronger than E308L?

Yes. ER308Si has a typical tensile strength of 600 MPa (87 ksi) against 570 MPa (82.7 ksi) for E308L — about 5% more.

Which is cheaper, E308L or ER308Si?

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

When should I choose E308L over ER308Si?

Pick ER308Si when strength drives the design.

Ready to make it?

Upload a CAD file and FabDigit prices the part in E308L and ER308Si 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.