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Stainless Steel 409 vs 409Cb

Stainless Steel · grade comparison

Stainless Steel 409 and 409Cb are both stainless steel grades. Both yield at about 250 MPa — strength does not separate them. 409Cb runs hotter in service (760°C vs 675°C continuous). On the shop floor, 409Cb sits in a lower cost tier (budget, $) than 409 (premium, $$$).

409CbChoose it when the part sees heat, or when cost is the deciding factor.

409 vs 409Cb: properties

409409Cb

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

450 MPa65.3 ksi
430 MPa62.4 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
255 MPa37 ksi

Elongation at Break

30%
32%

Compressive Strength

250 MPa36.3 ksi
260 MPa37.7 ksi

Shear Strength

280 MPa40.6 ksi
300 MPa43.5 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
240 MPa34.8 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
60 J44.3 ft·lbf

Hardness, Rockwell B

80 HRB
78 HRB

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 160 GPa23.2 Msi · Reduction in Area 65% · Hardness, Brinell 150 HB · Hardness, Vickers 155 HV

Physical

Density and transition temperatures.

Density

7.7 g/cm³0.28 lb/in³
7.75 g/cm³0.28 lb/in³

Melting Point (Solidus)

1,482°C2,700 °F
1,450°C2,642 °F

Liquidus Temperature

1,532°C2,790 °F
1,510°C2,750 °F

Thermal

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

Max Service Temperature (continuous)

675°C1,247 °F
760°C1,400 °F

Min Service Temperature

-20°C-4 °F
-40°C-40 °F

Same in both: Thermal Conductivity 24.9 W/m·K14.4 BTU/hr·ft·°F · Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 11.7 µm/m·K6.5 µin/in·°F · Latent Heat of Fusion 260 J/g112 BTU/lb

Electrical

Conductivity and insulation.

Same in both: Electrical Conductivity 2.9 % IACS · Electrical Resistivity 6×10⁻⁷ Ω·m23.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Corrosion Resistance

40 / 100
45 / 100

Same in both: Galvanic Potential (seawater, vs SCE) -0.35 V

Manufacturability

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

Weldability

80 / 100
85 / 100

Formability (cold)

78 / 100
72 / 100

Brazeability / Solderability

60 / 100
70 / 100

Polishability

55 / 100
50 / 100

Same in both: Machinability 55 / 100 · Machinability Rating (AISI 1212 = 100 %) 65%

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

2.9 kg CO₂/kg
2.7 kg CO₂/kg

Typical Recycled Content

65%
60%

Same in both: Embodied Energy (primary production) 40 MJ/kg17,197 BTU/lb · Embodied Water 90 L/kg10.8 gal/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

58 kN·m/kg
55 kN·m/kg

Specific Stiffness (E / density)

26 MN·m/kg
25.8 MN·m/kg

Modulus of Resilience

156 kJ/m³
163 kJ/m³

Same in both: Thermal Diffusivity 7 mm²/s · Thermal Shock Resistance Index 5

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 scale409Cb409

Manufacturing and finishing

Capability409409Cb
CNC machiningYes—
Sheet metalYes—
Default conditionAnnealed—
Relative cost$$$ Premium$ Budget
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
Black OxideYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CerakoteYes—
Chrome PlatingYes—
CrNYes—
DLCYes—
ElectropolishingYes—
HVOF CoatingYes—
MoS2Yes—
Multilayer CVDYes—
Nickel PlatingYes—
PTFE CoatingYes—
PaintingYes—
Passivation (Stainless Steel)Yes—

They share 7 finishes: Electroless Nickel (EN), Epoxy Coating, Gold Plating, Hard Chrome Plating, Pickling, Plasma Spray, Silver Plating.

409 vs 409Cb — frequently asked

What is the difference between 409 and 409Cb?

Stainless Steel 409 and 409Cb are both stainless steel grades. Both yield at about 250 MPa — strength does not separate them. 409Cb runs hotter in service (760°C vs 675°C continuous).

Which is cheaper, 409 or 409Cb?

409Cb is the lower-cost material: it sits in the budget tier ($) while 409 is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which welds better, 409 or 409Cb?

409Cb. Its weldability rates excellent (85/100) against very good (80/100) for 409.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 409 and 409Cb 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.