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Stainless Steel 1.4003 vs 409

Stainless Steel · grade comparison

Stainless Steel 1.4003 and 409 are both stainless steel grades. 1.4003 is the stronger of the two: yield strength 330 MPa (47.9 ksi) against 250 MPa (36.3 ksi) for 409, about 32% more; tensile strength follows at 490 MPa (71.1 ksi) vs 450 MPa (65.3 ksi). 1.4003 is harder — 160 HB against 150 HB for 409 — which matters for wear surfaces and threads. 409 runs hotter in service (675°C vs 550°C continuous) and 1.4003 conducts heat better (30 W/m·K vs 24.9 W/m·K). On the shop floor, 409 forms better (very good vs good) and 1.4003 sits in a lower cost tier (standard, $$) than 409 (premium, $$$).

1.4003Choose it when strength drives the design, or when surface hardness matters.

409Choose it when the part sees heat.

1.4003 vs 409: properties

1.4003409

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

210 GPa30.5 Msi
200 GPa29 Msi

Shear Modulus

81 GPa11.7 Msi
77 GPa11.2 Msi

Tensile Strength (Ultimate)

490 MPa71.1 ksi
450 MPa65.3 ksi

Yield Strength (0.2% offset)

330 MPa47.9 ksi
250 MPa36.3 ksi

Elongation at Break

28%
30%

Reduction in Area

60%
65%

Compressive Strength

330 MPa47.9 ksi
250 MPa36.3 ksi

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)

80 J59 ft·lbf
40 J29.5 ft·lbf

Hardness, Brinell

160 HB
150 HB

Hardness, Rockwell B

83 HRB
80 HRB

Hardness, Vickers

170 HV
155 HV

Same in both: Bulk Modulus 160 GPa23.2 Msi · Poisson's Ratio 0.3

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,450°C2,642 °F
1,482°C2,700 °F

Liquidus Temperature

1,510°C2,750 °F
1,532°C2,790 °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

30 W/m·K17.3 BTU/hr·ft·°F
24.9 W/m·K14.4 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

10.4 µm/m·K5.8 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)

550°C1,022 °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

42 / 100
40 / 100

Manufacturability

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

Machinability Rating (AISI 1212 = 100 %)

55%
65%

Weldability

75 / 100
80 / 100

Formability (cold)

58 / 100
78 / 100

Brazeability / Solderability

55 / 100
60 / 100

Polishability

50 / 100
55 / 100

Same in both: Machinability 55 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

38 MJ/kg16,337 BTU/lb
40 MJ/kg17,197 BTU/lb

Embodied Water

55 L/kg6.6 gal/lb
90 L/kg10.8 gal/lb

Typical Recycled Content

60%
65%

Same in both: Embodied Carbon (primary production) 2.9 kg CO₂/kg

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

64 kN·m/kg
58 kN·m/kg

Specific Stiffness (E / density)

27.3 MN·m/kg
26 MN·m/kg

Modulus of Resilience

259 kJ/m³
156 kJ/m³

Thermal Diffusivity

8.5 mm²/s
7 mm²/s

Thermal Shock Resistance Index

7
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 scale1.4003409

Manufacturing and finishing

Capability1.4003409
CNC machining—Yes
Sheet metal—Yes
Default condition—Annealed
Relative cost$$ Standard$$$ Premium
Min. machined wall—0.8 mm
Best machined surface—Ra 1.6 µm
AlCrN—Yes
AlTiN—Yes
Black Oxide—Yes
CVD Al2O3—Yes
CVD TiCN—Yes
CVD TiN—Yes
Cerakote—Yes
Chrome Plating—Yes
CrN—Yes
DLC—Yes
Electropolishing—Yes
HVOF Coating—Yes
MoS2—Yes
Multilayer CVD—Yes
Nickel Plating—Yes
PTFE Coating—Yes
Painting—Yes
Passivation (Stainless Steel)—Yes

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

1.4003 vs 409 — frequently asked

Is 1.4003 stronger than 409?

Yes. 1.4003 has a typical yield strength of 330 MPa (47.9 ksi) against 250 MPa (36.3 ksi) for 409 — about 32% more. Tensile strength is 490 MPa (71.1 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, 1.4003 or 409?

1.4003 is the lower-cost material: it sits in the standard 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, 1.4003 or 409?

409. Its weldability rates very good (80/100) against very good (75/100) for 1.4003.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 1.4003 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.