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Stainless Steel 409 vs 429

Stainless Steel · grade comparison

Stainless Steel 409 and 429 are both stainless steel grades. 429 is the stronger of the two: yield strength 310 MPa (45 ksi) against 250 MPa (36.3 ksi) for 409, about 24% more; tensile strength follows at 490 MPa (71.1 ksi) vs 450 MPa (65.3 ksi). 429 is harder — 160 HB against 150 HB for 409 — which matters for wear surfaces and threads. 429 runs hotter in service (815°C vs 675°C continuous). On the shop floor, 409 welds better (very good vs good) and 409 forms better (very good vs good).

409Choose it when it will be welded.

429Choose it when strength drives the design, or when surface hardness matters.

409 vs 429: properties

409429

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

450 MPa65.3 ksi
490 MPa71.1 ksi

Yield Strength (0.2% offset)

250 MPa36.3 ksi
310 MPa45 ksi

Reduction in Area

65%
60%

Compressive Strength

250 MPa36.3 ksi
—

Shear Strength

280 MPa40.6 ksi
340 MPa49.3 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
160 HB

Hardness, Rockwell B

80 HRB
83 HRB

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 · Poisson's Ratio 0.3 · Elongation at Break 30%

Physical

Density and transition temperatures.

Melting Point (Solidus)

1,482°C2,700 °F
1,427°C2,601 °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
25 W/m·K14.4 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

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

Max Service Temperature (continuous)

675°C1,247 °F
815°C1,499 °F

Min Service Temperature

-20°C-4 °F
-30°C-22 °F

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

Galvanic Potential (seawater, vs SCE)

-0.35 V
-0.2 V

Corrosion Resistance

40 / 100
43 / 100

Manufacturability

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

Machinability

55 / 100
52 / 100

Machinability Rating (AISI 1212 = 100 %)

65%
55%

Weldability

80 / 100
60 / 100

Formability (cold)

78 / 100
65 / 100

Polishability

55 / 100
65 / 100

Same in both: Brazeability / Solderability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

40 MJ/kg17,197 BTU/lb
47 MJ/kg20,206 BTU/lb

Embodied Carbon (primary production)

2.9 kg CO₂/kg
3.5 kg CO₂/kg

Embodied Water

90 L/kg10.8 gal/lb
120 L/kg14.4 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
64 kN·m/kg

Modulus of Resilience

156 kJ/m³
240 kJ/m³

Thermal Diffusivity

7 mm²/s
7.1 mm²/s

Thermal Shock Resistance Index

5
6

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

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 scale409429

Manufacturing and finishing

Capability409429
CNC machiningYes—
Default conditionAnnealedAnnealed
Relative cost$$$ Premium$$$ Premium
Min. machined wall0.8 mm—
Best machined surfaceRa 1.6 µm—
AlCrNYes—
AlTiNYes—
CVD Al2O3Yes—
CVD TiCNYes—
CVD TiNYes—
CrNYes—
DLCYes—
HVOF CoatingYes—
MoS2Yes—
Multilayer CVDYes—
TiAlNYes—
TiB2Yes—
TiCNYes—
TiNYes—
WC/CYes—
ZrNYes—

Both are offered for Sheet metal. They share 16 finishes: Black Oxide, Cerakote, Chrome Plating, Electroless Nickel (EN), Electropolishing, Epoxy Coating, Gold Plating, Hard Chrome Plating, Nickel Plating, PTFE Coating, Painting, Passivation (Stainless Steel) and 4 more.

409 vs 429 — frequently asked

Is 429 stronger than 409?

Yes. 429 has a typical yield strength of 310 MPa (45 ksi) against 250 MPa (36.3 ksi) for 409 — about 24% more. Tensile strength is 490 MPa (71.1 ksi) vs 450 MPa (65.3 ksi).

Which is cheaper, 409 or 429?

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, 409 or 429?

409. Its weldability rates very good (80/100) against good (60/100) for 429.

Ready to make it?

Upload a CAD file and FabDigit prices the part in 409 and 429 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.