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Stainless Steel E309L vs ER308

Stainless Steel · grade comparison

Stainless Steel E309L and ER308 are both stainless steel grades. ER308 is the stronger of the two: tensile strength 600 MPa (87 ksi) against 570 MPa (82.7 ksi) for E309L, about 5% more.

ER308Choose it when strength drives the design.

E309L vs ER308: properties

E309LER308

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Poisson's Ratio

0.29
0.3

Tensile Strength (Ultimate)

570 MPa82.7 ksi
600 MPa87 ksi

Elongation at Break

38%
40%

Reduction in Area

50%
55%

Charpy V-Notch Impact (RT)

55 J40.6 ft·lbf
90 J66.4 ft·lbf

Hardness, Brinell

190 HB
185 HB

Hardness, Rockwell B

88 HRB
90 HRB

Hardness, Vickers

200 HV
195 HV

Same in both: Elastic (Young's) Modulus 195 GPa28.3 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 145 GPa21 Msi · Yield Strength (0.2% offset) 400 MPa58 ksi · Compressive Strength 400 MPa58 ksi · Shear Strength 400 MPa58 ksi · Fatigue Strength (Endurance Limit) 240 MPa34.8 ksi · Fracture Toughness (K_IC) 150 MPa·√m137 ksi·√in

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 Conductivity

15 W/m·K8.7 BTU/hr·ft·°F
15.5 W/m·K9 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

15 µm/m·K8.3 µin/in·°F
16.9 µm/m·K9.4 µin/in·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
280 J/g120 BTU/lb

Max Service Temperature (continuous)

800°C1,472 °F
760°C1,400 °F

Min Service Temperature

-100°C-148 °F
-196°C-321 °F

Same in both: Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.2 % IACS
2.4 % IACS

Electrical Resistivity

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

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.05 V
-0.08 V

Corrosion Resistance

68 / 100
65 / 100

Manufacturability

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

Machinability

40 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

40%
45%

Weldability

90 / 100
95 / 100

Brazeability / Solderability

50 / 100
60 / 100

Polishability

55 / 100
70 / 100

Formability (cold)

—
55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

60 MJ/kg25,795 BTU/lb
57 MJ/kg24,506 BTU/lb

Embodied Carbon (primary production)

5.2 kg CO₂/kg
5 kg CO₂/kg

Embodied Water

110 L/kg13.2 gal/lb
130 L/kg15.6 gal/lb

Typical Recycled Content

60%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

72 kN·m/kg
76 kN·m/kg

Thermal Diffusivity

3.8 mm²/s
3.9 mm²/s

Same in both: Specific Stiffness (E / density) 24.7 MN·m/kg · Modulus of Resilience 410 kJ/m³ · 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 scaleER308E309L

Manufacturing and finishing

CapabilityE309LER308
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.

E309L vs ER308 — frequently asked

Is ER308 stronger than E309L?

Yes. ER308 has a typical tensile strength of 600 MPa (87 ksi) against 570 MPa (82.7 ksi) for E309L — about 5% more.

Which is cheaper, E309L or ER308?

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.

Which welds better, E309L or ER308?

ER308. Its weldability rates excellent (95/100) against excellent (90/100) for E309L.

Ready to make it?

Upload a CAD file and FabDigit prices the part in E309L and ER308 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.