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Stainless Steel 409 vs S44537

Stainless Steel · grade comparison

Stainless Steel 409 and S44537 are both stainless steel grades. S44537 is the stronger of the two: yield strength 350 MPa (50.8 ksi) against 250 MPa (36.3 ksi) for 409, about 40% more; tensile strength follows at 510 MPa (74 ksi) vs 450 MPa (65.3 ksi). In exchange, 409 is the more ductile: elongation 30% versus 24% for S44537, and S44537 is harder (175 HB vs 150 HB). S44537 runs hotter in service (1,000°C vs 675°C continuous) and 409 conducts heat better (24.9 W/m·K vs 20.5 W/m·K). On the shop floor, 409 machines more easily (good vs fair) and 409 welds better (very good vs good).

409Choose it when the part is bent, formed or impact-loaded, or when the part is machined in volume.

S44537Choose it when strength drives the design, or when the part sees heat.

409 vs S44537: properties

409S44537

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Bulk Modulus

160 GPa23.2 Msi
158 GPa22.9 Msi

Tensile Strength (Ultimate)

450 MPa65.3 ksi
510 MPa74 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
350 MPa50.8 ksi

Elongation at Break

30%
24%

Reduction in Area

65%
60%

Compressive Strength

250 MPa36.3 ksi
350 MPa50.8 ksi

Shear Strength

280 MPa40.6 ksi
320 MPa46.4 ksi

Fatigue Strength (Endurance Limit)

230 MPa33.4 ksi
250 MPa36.3 ksi

Charpy V-Notch Impact (RT)

40 J29.5 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

150 HB
175 HB

Hardness, Rockwell B

80 HRB
85 HRB

Hardness, Vickers

155 HV
185 HV

Fracture Toughness (K_IC)

—
55 MPa·√m50.1 ksi·√in

Same in both: Elastic (Young's) Modulus 200 GPa29 Msi · Shear Modulus 77 GPa11.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,482°C2,700 °F
1,425°C2,597 °F

Liquidus Temperature

1,532°C2,790 °F
1,510°C2,750 °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
20.5 W/m·K11.8 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

Max Service Temperature (continuous)

675°C1,247 °F
1,000°C1,832 °F

Same in both: Specific Heat Capacity 460 J/kg·K0.11 BTU/lb·°F · Latent Heat of Fusion 260 J/g112 BTU/lb · Min Service Temperature -20°C-4 °F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.9 % IACS
2.6 % IACS

Electrical Resistivity

6×10⁻⁷ Ω·m23.6 µΩ·in
6.7×10⁻⁷ Ω·m26.4 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
66 / 100

Manufacturability

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

Machinability

55 / 100
45 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
50%

Weldability

80 / 100
55 / 100

Formability (cold)

78 / 100
58 / 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 kg CO₂/kg

Embodied Water

90 L/kg10.8 gal/lb
200 L/kg24 gal/lb

Same in both: Typical Recycled Content 65%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

58 kN·m/kg
66 kN·m/kg

Modulus of Resilience

156 kJ/m³
306 kJ/m³

Thermal Diffusivity

7 mm²/s
5.8 mm²/s

Same in both: Specific Stiffness (E / density) 26 MN·m/kg · 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 scaleS44537409

Manufacturing and finishing

Capability409S44537
CNC machiningYes—
Sheet metalYes—
Default conditionAnnealed—
Relative cost$$$ Premium$$$ Premium
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 S44537 — frequently asked

Is S44537 stronger than 409?

Yes. S44537 has a typical yield strength of 350 MPa (50.8 ksi) against 250 MPa (36.3 ksi) for 409 — about 40% more. Tensile strength is 510 MPa (74 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, 409 or S44537?

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, 409 or S44537?

409. Its machinability rates good (55/100) against fair (45/100) for S44537; for welding the order is 409 first (very good, 80/100) then S44537 (good, 55/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 409 and S44537 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.