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Stainless Steel E3155 vs ER308

Stainless Steel · grade comparison

Stainless Steel E3155 and ER308 are both stainless steel grades. E3155 is the stronger of the two: yield strength 460 MPa (66.7 ksi) against 400 MPa (58 ksi) for ER308, about 15% more; tensile strength follows at 760 MPa (110 ksi) vs 600 MPa (87 ksi). In exchange, ER308 is the more ductile: elongation 40% versus 25% for E3155, and E3155 is harder (215 HB vs 185 HB). ER308 is lighter (7.9 g/cm³ vs 8.19 g/cm³ for E3155) and ER308 conducts heat better (15.5 W/m·K vs 12.6 W/m·K). On the shop floor, ER308 machines more easily (fair vs poor), ER308 welds better (excellent vs very good), and ER308 sits in a lower cost tier (premium, $$$) than E3155 (high, $$$$).

E3155Choose it when strength drives the design.

ER308Choose it when the part is bent, formed or impact-loaded, or when weight is the constraint.

E3155 vs ER308: properties

E3155ER308

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
195 GPa28.3 Msi

Bulk Modulus

167 GPa24.2 Msi
145 GPa21 Msi

Tensile Strength (Ultimate)

760 MPa110 ksi
600 MPa87 ksi

Yield Strength (0.2% offset)

460 MPa66.7 ksi
400 MPa58 ksi

Elongation at Break

25%
40%

Reduction in Area

30%
55%

Shear Strength

480 MPa69.6 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

290 MPa42.1 ksi
240 MPa34.8 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
90 J66.4 ft·lbf

Hardness, Brinell

215 HB
185 HB

Hardness, Rockwell B

95 HRB
90 HRB

Hardness, Vickers

225 HV
195 HV

Compressive Strength

—
400 MPa58 ksi

Fracture Toughness (K_IC)

—
150 MPa·√m137 ksi·√in

Same in both: Shear Modulus 77 GPa11.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Density

8.19 g/cm³0.3 lb/in³
7.9 g/cm³0.29 lb/in³

Melting Point (Solidus)

1,288°C2,350 °F
1,400°C2,552 °F

Liquidus Temperature

1,354°C2,469 °F
1,450°C2,642 °F

Thermal

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

Thermal Conductivity

12.6 W/m·K7.3 BTU/hr·ft·°F
15.5 W/m·K9 BTU/hr·ft·°F

Specific Heat Capacity

430 J/kg·K0.1 BTU/lb·°F
500 J/kg·K0.12 BTU/lb·°F

Thermal Expansion (CTE, 20–100 °C)

14.4 µm/m·K8 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)

815°C1,499 °F
760°C1,400 °F

Same in both: Min Service Temperature -196°C-321 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

1.9 % IACS
2.4 % IACS

Electrical Resistivity

9.1×10⁻⁷ Ω·m35.8 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)

-0.1 V
-0.08 V

Corrosion Resistance

66 / 100
65 / 100

Manufacturability

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

Machinability

16 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

12%
45%

Weldability

70 / 100
95 / 100

Formability (cold)

35 / 100
55 / 100

Brazeability / Solderability

45 / 100
60 / 100

Polishability

60 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

125 MJ/kg53,740 BTU/lb
57 MJ/kg24,506 BTU/lb

Embodied Carbon (primary production)

9.5 kg CO₂/kg
5 kg CO₂/kg

Embodied Water

220 L/kg26.4 gal/lb
130 L/kg15.6 gal/lb

Typical Recycled Content

30%
45%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

93 kN·m/kg
76 kN·m/kg

Specific Stiffness (E / density)

24.4 MN·m/kg
24.7 MN·m/kg

Modulus of Resilience

529 kJ/m³
410 kJ/m³

Thermal Diffusivity

3.6 mm²/s
3.9 mm²/s

Same in both: 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 scaleER308E3155

Manufacturing and finishing

CapabilityE3155ER308
Default condition——
Relative cost$$$$ High$$$ 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.

E3155 vs ER308 — frequently asked

Is E3155 stronger than ER308?

Yes. E3155 has a typical yield strength of 460 MPa (66.7 ksi) against 400 MPa (58 ksi) for ER308 — about 15% more. Tensile strength is 760 MPa (110 ksi) vs 600 MPa (87 ksi).

Which is cheaper, E3155 or ER308?

ER308 is the lower-cost material: it sits in the premium tier ($$$) while E3155 is high ($$$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, E3155 or ER308?

ER308. Its machinability rates fair (38/100) against poor (16/100) for E3155; for welding the order is ER308 first (excellent, 95/100) then E3155 (very good, 70/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in E3155 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.