FabDigitFabDigit

Stainless Steel 303 vs 304N

Stainless Steel · grade comparison

Stainless Steel 303 and 304N are both stainless steel grades. 303 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 320 MPa (46.4 ksi) for 304N, about 41% more. In exchange, 304N is the more ductile: elongation 50% versus 30% for 303, and 303 is harder (240 HB vs 180 HB). On the shop floor, 303 machines more easily (very good vs fair), 304N welds better (excellent vs poor), and 304N sits in a lower cost tier (standard, $$) than 303 (premium, $$$).

303Choose it when strength drives the design, or when the part is machined in volume.

304NChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

303 vs 304N: properties

303304N

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Tensile Strength (Ultimate)

655 MPa95 ksi
650 MPa94.3 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
320 MPa46.4 ksi

Elongation at Break

30%
50%

Reduction in Area

50%
65%

Compressive Strength

450 MPa65.3 ksi
320 MPa46.4 ksi

Shear Strength

420 MPa60.9 ksi
435 MPa63.1 ksi

Fatigue Strength (Endurance Limit)

270 MPa39.2 ksi
260 MPa37.7 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
210 MPa·√m191 ksi·√in

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
160 J118 ft·lbf

Hardness, Brinell

240 HB
180 HB

Hardness, Rockwell B

99 HRB
88 HRB

Hardness, Vickers

250 HV
190 HV

Same in both: Elastic (Young's) Modulus 193 GPa28 Msi · Shear Modulus 77 GPa11.2 Msi · Bulk Modulus 140 GPa20.3 Msi · Poisson's Ratio 0.29

Physical

Density and transition temperatures.

Liquidus Temperature

1,420°C2,588 °F
1,450°C2,642 °F

Same in both: Density 7.9 g/cm³0.29 lb/in³ · Melting Point (Solidus) 1,400°C2,552 °F

Thermal

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

Latent Heat of Fusion

275 J/g118 BTU/lb
270 J/g116 BTU/lb

Min Service Temperature

-100°C-148 °F
-196°C-321 °F

Same in both: Thermal Conductivity 16.2 W/m·K9.4 BTU/hr·ft·°F · Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Thermal Expansion (CTE, 20–100 °C) 17.3 µm/m·K9.6 µin/in·°F · Max Service Temperature (continuous) 760°C1,400 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

7.2×10⁻⁷ Ω·m28.3 µΩ·in
7.4×10⁻⁷ Ω·m29.1 µΩ·in

Same in both: Electrical Conductivity 2.4 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.1 V
-0.08 V

Corrosion Resistance

58 / 100
62 / 100

Manufacturability

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

Machinability

72 / 100
38 / 100

Machinability Rating (AISI 1212 = 100 %)

78%
40%

Weldability

25 / 100
85 / 100

Formability (cold)

40 / 100
78 / 100

Brazeability / Solderability

60 / 100
70 / 100

Polishability

40 / 100
85 / 100

Castability

—
45 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

53 MJ/kg22,786 BTU/lb
55 MJ/kg23,646 BTU/lb

Embodied Carbon (primary production)

5.5 kg CO₂/kg
5.2 kg CO₂/kg

Embodied Water

150 L/kg18 gal/lb
250 L/kg30 gal/lb

Same in both: Typical Recycled Content 65%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

83 kN·m/kg
82 kN·m/kg

Modulus of Resilience

525 kJ/m³
265 kJ/m³

Same in both: Specific Stiffness (E / density) 24.4 MN·m/kg · Thermal Diffusivity 4.1 mm²/s · Thermal Shock Resistance Index 3

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 scale303304N

Manufacturing and finishing

Capability303304N
CNC machiningYes—
Default conditionCold Drawn—
Relative cost$$$ Premium$$ Standard
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.

303 vs 304N — frequently asked

Is 303 stronger than 304N?

Yes. 303 has a typical yield strength of 450 MPa (65.3 ksi) against 320 MPa (46.4 ksi) for 304N — about 41% more. Tensile strength is 655 MPa (95 ksi) vs 650 MPa (94.3 ksi).

Which is cheaper, 303 or 304N?

304N is the lower-cost material: it sits in the standard tier ($$) while 303 is premium ($$$). Part price depends far more on geometry, tolerance and quantity than on raw stock — upload a CAD file for a live quote.

Which is easier to machine, 303 or 304N?

303. Its machinability rates very good (72/100) against fair (38/100) for 304N; for welding the order is 304N first (excellent, 85/100) then 303 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 303 and 304N 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.