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Stainless Steel E317 vs ER308

Stainless Steel · grade comparison

Stainless Steel E317 and ER308 are both stainless steel grades. E317 is the stronger of the two: yield strength 440 MPa (63.8 ksi) against 400 MPa (58 ksi) for ER308, about 10% more. On the shop floor, ER308 welds better (95 vs 85 out of 100) and ER308 sits in a lower cost tier (premium, $$$) than E317 (high, $$$$).

E317Choose it when strength drives the design.

ER308Choose it when it will be welded, or when cost is the deciding factor.

E317 vs ER308: properties

E317ER308

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Shear Modulus

76 GPa11 Msi
77 GPa11.2 Msi

Bulk Modulus

160 GPa23.2 Msi
145 GPa21 Msi

Poisson's Ratio

0.29
0.3

Yield Strength (0.2% offset)

440 MPa63.8 ksi
400 MPa58 ksi

Elongation at Break

38%
40%

Reduction in Area

50%
55%

Compressive Strength

440 MPa63.8 ksi
400 MPa58 ksi

Fracture Toughness (K_IC)

120 MPa·√m109 ksi·√in
150 MPa·√m137 ksi·√in

Charpy V-Notch Impact (RT)

60 J44.3 ft·lbf
90 J66.4 ft·lbf

Same in both: Elastic (Young's) Modulus 195 GPa28.3 Msi · Tensile Strength (Ultimate) 600 MPa87 ksi · Shear Strength 400 MPa58 ksi · Fatigue Strength (Endurance Limit) 240 MPa34.8 ksi · Hardness, Brinell 185 HB · Hardness, Rockwell B 90 HRB · Hardness, Vickers 195 HV

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,370°C2,498 °F
1,400°C2,552 °F

Liquidus Temperature

1,400°C2,552 °F
1,450°C2,642 °F

Thermal

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

Thermal Conductivity

14.4 W/m·K8.3 BTU/hr·ft·°F
15.5 W/m·K9 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

16 µm/m·K8.9 µin/in·°F
16.9 µm/m·K9.4 µin/in·°F

Latent Heat of Fusion

275 J/g118 BTU/lb
280 J/g120 BTU/lb

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 · Max Service Temperature (continuous) 760°C1,400 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.2 % IACS
2.4 % IACS

Electrical Resistivity

7.9×10⁻⁷ Ω·m31.1 µΩ·in
7.4×10⁻⁷ Ω·m29.1 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

74 / 100
65 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.08 V

Manufacturability

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

Machinability

33 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

35%
45%

Weldability

85 / 100
95 / 100

Brazeability / Solderability

55 / 100
60 / 100

Same in both: Formability (cold) 55 / 100 · Polishability 70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

62 MJ/kg26,655 BTU/lb
57 MJ/kg24,506 BTU/lb

Embodied Carbon (primary production)

5.2 kg CO₂/kg
5 kg CO₂/kg

Embodied Water

160 L/kg19.2 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)

75 kN·m/kg
76 kN·m/kg

Specific Stiffness (E / density)

24.4 MN·m/kg
24.7 MN·m/kg

Modulus of Resilience

496 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 scaleER308E317

Manufacturing and finishing

CapabilityE317ER308
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.

E317 vs ER308 — frequently asked

Is E317 stronger than ER308?

Yes. E317 has a typical yield strength of 440 MPa (63.8 ksi) against 400 MPa (58 ksi) for ER308 — about 10% more. Tensile strength is 600 MPa (87 ksi) vs 600 MPa (87 ksi).

Which is cheaper, E317 or ER308?

ER308 is the lower-cost material: it sits in the premium tier ($$$) while E317 is high ($$$$). 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, E317 or ER308?

ER308. Its machinability rates fair (38/100) against poor (33/100) for E317; for welding the order is ER308 first (excellent, 95/100) then E317 (excellent, 85/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in E317 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.