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Stainless Steel 409 vs S32803

Stainless Steel · grade comparison

Stainless Steel 409 and S32803 are both stainless steel grades. S32803 is the stronger of the two: yield strength 520 MPa (75.4 ksi) against 250 MPa (36.3 ksi) for 409, about 108% more; tensile strength follows at 640 MPa (92.8 ksi) vs 450 MPa (65.3 ksi). In exchange, 409 is the more ductile: elongation 30% versus 25% for S32803, and S32803 is harder (195 HB vs 150 HB). 409 runs hotter in service (675°C vs 300°C continuous) and 409 conducts heat better (24.9 W/m·K vs 16 W/m·K). On the shop floor, 409 machines more easily (good vs poor), 409 welds better (very good vs fair), and 409 sits in a lower cost tier (premium, $$$) than S32803 (high, $$$$).

409Choose it when the part is bent, formed or impact-loaded, or when the part sees heat.

S32803Choose it when strength drives the design.

409 vs S32803: properties

409S32803

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
205 GPa29.7 Msi

Shear Modulus

77 GPa11.2 Msi
79 GPa11.5 Msi

Poisson's Ratio

0.3
0.29

Tensile Strength (Ultimate)

450 MPa65.3 ksi
640 MPa92.8 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
520 MPa75.4 ksi

Elongation at Break

30%
25%

Reduction in Area

65%
55%

Compressive Strength

250 MPa36.3 ksi
—

Shear Strength

280 MPa40.6 ksi
400 MPa58 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
340 MPa49.3 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
50 J36.9 ft·lbf

Hardness, Brinell

150 HB
195 HB

Hardness, Rockwell B

80 HRB
92 HRB

Hardness, Vickers

155 HV
205 HV

Fracture Toughness (K_IC)

—
70 MPa·√m63.7 ksi·√in

Same in both: Bulk Modulus 160 GPa23.2 Msi

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,482°C2,700 °F
1,420°C2,588 °F

Liquidus Temperature

1,532°C2,790 °F
1,490°C2,714 °F

Same in both: Density 7.7 g/cm³0.28 lb/in³

Thermal

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

Thermal Conductivity

24.9 W/m·K14.4 BTU/hr·ft·°F
16 W/m·K9.2 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

11.7 µm/m·K6.5 µin/in·°F
10.5 µm/m·K5.8 µin/in·°F

Latent Heat of Fusion

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

Max Service Temperature (continuous)

675°C1,247 °F
300°C572 °F

Min Service Temperature

-20°C-4 °F
-45°C-49 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.9 % IACS
2.6 % IACS

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 µΩ·in
6.5×10⁻⁷ Ω·m25.6 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.35 V
-0.15 V

Corrosion Resistance

40 / 100
82 / 100

Manufacturability

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

Machinability

55 / 100
28 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
35%

Weldability

80 / 100
45 / 100

Formability (cold)

78 / 100
50 / 100

Brazeability / Solderability

60 / 100
55 / 100

Polishability

55 / 100
70 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

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

Embodied Carbon (primary production)

2.9 kg CO₂/kg
4.5 kg CO₂/kg

Embodied Water

90 L/kg10.8 gal/lb
80 L/kg9.6 gal/lb

Typical Recycled Content

65%
40%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

58 kN·m/kg
83 kN·m/kg

Specific Stiffness (E / density)

26 MN·m/kg
26.6 MN·m/kg

Modulus of Resilience

156 kJ/m³
660 kJ/m³

Thermal Diffusivity

7 mm²/s
4.5 mm²/s

Same in both: 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 scaleS32803409

Manufacturing and finishing

Capability409S32803
CNC machiningYes—
Sheet metalYes—
Default conditionAnnealed—
Relative cost$$$ Premium$$$$ High
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 S32803 — frequently asked

Is S32803 stronger than 409?

Yes. S32803 has a typical yield strength of 520 MPa (75.4 ksi) against 250 MPa (36.3 ksi) for 409 — about 108% more. Tensile strength is 640 MPa (92.8 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, 409 or S32803?

409 is the lower-cost material: it sits in the premium tier ($$$) while S32803 is high ($$$$). 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, 409 or S32803?

409. Its machinability rates good (55/100) against poor (28/100) for S32803; for welding the order is 409 first (very good, 80/100) then S32803 (fair, 45/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 409 and S32803 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.