Stainless Steel ER308H vs ER409Cb
Stainless Steel · grade comparison
Stainless Steel ER308H and ER409Cb are both stainless steel grades. ER308H is the stronger of the two: yield strength 415 MPa (60.2 ksi) against 330 MPa (47.9 ksi) for ER409Cb, about 26% more; tensile strength follows at 590 MPa (85.6 ksi) vs 480 MPa (69.6 ksi). ER308H is the more ductile: elongation 38% versus 22% for ER409Cb, and ER308H is harder (175 HB vs 165 HB). ER308H runs hotter in service (800°C vs 675°C continuous) and ER409Cb conducts heat better (24.9 W/m·K vs 16.2 W/m·K). On the shop floor, ER409Cb machines more easily (good vs fair).
ER308HChoose it when strength drives the design, or when the part is bent, formed or impact-loaded.
ER409CbChoose it when the part is machined in volume.
ER308H vs ER409Cb: 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.
Elastic (Young's) Modulus
Poisson's Ratio
Tensile Strength (Ultimate)
Yield Strength (0.2% offset)
Elongation at Break
Reduction in Area
Compressive Strength
Shear Strength
Fatigue Strength (Endurance Limit)
Fracture Toughness (K_IC)
Charpy V-Notch Impact (RT)
Hardness, Brinell
Hardness, Rockwell B
Hardness, Vickers
Same in both: Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 160 GPa23.2 Msi
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
Specific Heat Capacity
Thermal Expansion (CTE, 20–100 °C)
Latent Heat of Fusion
Max Service Temperature (continuous)
Min Service Temperature
Electrical
Conductivity and insulation.
Electrical Conductivity
Electrical Resistivity
Chemical & Environmental
Corrosion and environmental resistance (0–100 scores).
Galvanic Potential (seawater, vs SCE)
Corrosion Resistance
Manufacturability
FabDigit workshop ratings (0–100 scores) — how each material behaves on the machine.
Machinability
Machinability Rating (AISI 1212 = 100 %)
Weldability
Formability (cold)
Polishability
Same in both: Brazeability / Solderability 60 / 100
Sustainability
Primary-production footprint per kilogram.
Embodied Energy (primary production)
Embodied Carbon (primary production)
Embodied Water
Same in both: Typical Recycled Content 60%
Common Calculations
Ratios derived from the values above.
Specific Strength (UTS / density)
Specific Stiffness (E / density)
Modulus of Resilience
Thermal Diffusivity
Thermal Shock Resistance Index
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 | ER308H | ER409Cb |
|---|---|---|
| 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.
ER308H vs ER409Cb — frequently asked
Is ER308H stronger than ER409Cb?
Yes. ER308H has a typical yield strength of 415 MPa (60.2 ksi) against 330 MPa (47.9 ksi) for ER409Cb — about 26% more. Tensile strength is 590 MPa (85.6 ksi) vs 480 MPa (69.6 ksi).
Which is cheaper, ER308H or ER409Cb?
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 is easier to machine, ER308H or ER409Cb?
ER409Cb. Its machinability rates good (55/100) against fair (38/100) for ER308H; for welding the order is ER308H first (excellent, 88/100) then ER409Cb (very good, 80/100).
Ready to make it?
Upload a CAD file and FabDigit prices the part in ER308H and ER409Cb 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.