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Stainless Steel 405 vs 409

Stainless Steel · grade comparison

Stainless Steel 405 and 409 are both stainless steel grades, both heat resistant ss. 405 is the stronger of the two: yield strength 280 MPa (40.6 ksi) against 250 MPa (36.3 ksi) for 409, about 12% more; tensile strength follows at 480 MPa (69.6 ksi) vs 450 MPa (65.3 ksi). On the shop floor, 409 welds better (80 vs 70 out of 100) and 409 forms better (very good vs good).

405Choose it when strength drives the design.

409Choose it when it will be welded.

405 vs 409: properties

405409

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Poisson's Ratio

0.28
0.3

Tensile Strength (Ultimate)

480 MPa69.6 ksi
450 MPa65.3 ksi

Yield Strength (0.2% offset)

280 MPa40.6 ksi
250 MPa36.3 ksi

Elongation at Break

28%
30%

Reduction in Area

60%
65%

Shear Strength

310 MPa45 ksi
280 MPa40.6 ksi

Fatigue Strength (Endurance Limit)

240 MPa34.8 ksi
230 MPa33.4 ksi

Charpy V-Notch Impact (RT)

25 J18.4 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

155 HB
150 HB

Hardness, Rockwell B

82 HRB
80 HRB

Compressive Strength

—
250 MPa36.3 ksi

Hardness, Vickers

—
155 HV

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 160 GPa23.2 Msi

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,480°C2,696 °F
1,482°C2,700 °F

Liquidus Temperature

1,530°C2,786 °F
1,532°C2,790 °F

Thermal

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

Thermal Conductivity

27 W/m·K15.6 BTU/hr·ft·°F
24.9 W/m·K14.4 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10.8 µm/m·K6 µin/in·°F
11.7 µm/m·K6.5 µin/in·°F

Latent Heat of Fusion

270 J/g116 BTU/lb
260 J/g112 BTU/lb

Max Service Temperature (continuous)

705°C1,301 °F
675°C1,247 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Min Service Temperature -20°C-4 °F

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).

Galvanic Potential (seawater, vs SCE)

-0.3 V
-0.35 V

Corrosion Resistance

45 / 100
40 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

60%
65%

Weldability

70 / 100
80 / 100

Formability (cold)

60 / 100
78 / 100

Castability

40 / 100
—

Brazeability / Solderability

55 / 100
60 / 100

Polishability

60 / 100
55 / 100

Same in both: Machinability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

50 MJ/kg21,496 BTU/lb
40 MJ/kg17,197 BTU/lb

Embodied Carbon (primary production)

3.6 kg CO₂/kg
2.9 kg CO₂/kg

Embodied Water

140 L/kg16.8 gal/lb
90 L/kg10.8 gal/lb

Same in both: Typical Recycled Content 65%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

62 kN·m/kg
58 kN·m/kg

Specific Stiffness (E / density)

25.8 MN·m/kg
26 MN·m/kg

Modulus of Resilience

196 kJ/m³
156 kJ/m³

Thermal Diffusivity

7.6 mm²/s
7 mm²/s

Thermal Shock Resistance Index

6
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 scale405409

Manufacturing and finishing

Capability405409
Default conditionAnnealedAnnealed
Relative cost$$$ Premium$$$ Premium
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining and Sheet metal. Both take the same 32 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, CrN, DLC, Electroless Nickel (EN), Electropolishing and 20 more.

405 vs 409 — frequently asked

Is 405 stronger than 409?

Yes. 405 has a typical yield strength of 280 MPa (40.6 ksi) against 250 MPa (36.3 ksi) for 409 — about 12% more. Tensile strength is 480 MPa (69.6 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, 405 or 409?

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 welds better, 405 or 409?

409. Its weldability rates very good (80/100) against very good (70/100) for 405.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 405 and 409 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.