Stainless Steel E317 vs ER308Si
Stainless Steel · grade comparison
Stainless Steel E317 and ER308Si 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 ER308Si, about 10% more. E317 is harder — 185 HB against 175 HB for ER308Si — which matters for wear surfaces and threads. On the shop floor, ER308Si welds better (95 vs 85 out of 100) and ER308Si sits in a lower cost tier (premium, $$$) than E317 (high, $$$$).
E317Choose it when strength drives the design, or when surface hardness matters.
ER308SiChoose it when it will be welded, or when cost is the deciding factor.
E317 vs ER308Si: propertiesHow to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
How to read these bars
- One bar per material. A full bar is the highest value among all stainless steel grades in the FabDigit library; each bar is drawn as a share of that.
- The better value (by the usual engineering direction) is in bold. Rows with no direction — density, thermal conductivity — have no bold.
- Values are typical room-temperature figures for the condition named on each card.
- Confirm against the certified mill or resin datasheet before design release.
Mechanical
Strength, stiffness, ductility and hardness at room temperature.
Shear Modulus
Yield Strength (0.2% offset)
Reduction in Area
Compressive Strength
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Elastic (Young's) Modulus 195 GPa28.3 Msi · Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.29 · Tensile Strength (Ultimate) 600 MPa87 ksi · Elongation at Break 38% · Shear Strength 400 MPa58 ksi · Fatigue Strength (Endurance Limit) 240 MPa34.8 ksi
Physical
Density and transition temperatures.
Density
Melting Point (Solidus)
Liquidus Temperature
Thermal
How each material carries heat and how hot it can run.
Thermal Conductivity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Min Service Temperature
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
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Corrosion Resistance
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
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Brazeability / Solderability
Same in both: Polishability 70 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Typical Recycled Content
Common Calculations
Ratios derived from the values above.
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Same in both: Specific Strength (UTS / density) 75 kN·m/kg · 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.
Manufacturing and finishing
| Capability | E317 | ER308Si |
|---|---|---|
| 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 ER308Si — frequently asked
Is E317 stronger than ER308Si?
Yes. E317 has a typical yield strength of 440 MPa (63.8 ksi) against 400 MPa (58 ksi) for ER308Si — about 10% more. Tensile strength is 600 MPa (87 ksi) vs 600 MPa (87 ksi).
Which is cheaper, E317 or ER308Si?
ER308Si 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 ER308Si?
ER308Si. Its machinability rates fair (40/100) against poor (33/100) for E317; for welding the order is ER308Si 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 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.