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Stainless Steel 301LN vs 303

Stainless Steel · grade comparison

Stainless Steel 301LN and 303 are both stainless steel grades. 303 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 400 MPa (58 ksi) for 301LN, about 13% more. In exchange, 301LN is the more ductile: elongation 50% versus 30% for 303, and 303 is harder (240 HB vs 215 HB). On the shop floor, 303 machines more easily (very good vs fair), 301LN welds better (very good vs poor), and 301LN sits in a lower cost tier (standard, $$) than 303 (premium, $$$).

301LNChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

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

301LN vs 303: properties

301LN303

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

200 GPa29 Msi
193 GPa28 Msi

Bulk Modulus

145 GPa21 Msi
140 GPa20.3 Msi

Poisson's Ratio

0.28
0.29

Tensile Strength (Ultimate)

750 MPa109 ksi
655 MPa95 ksi

Yield Strength (0.2% offset)

400 MPa58 ksi
450 MPa65.3 ksi

Elongation at Break

50%
30%

Reduction in Area

65%
50%

Shear Strength

460 MPa66.7 ksi
420 MPa60.9 ksi

Fatigue Strength (Endurance Limit)

350 MPa50.8 ksi
270 MPa39.2 ksi

Fracture Toughness (K_IC)

160 MPa·√m146 ksi·√in
100 MPa·√m91 ksi·√in

Charpy V-Notch Impact (RT)

190 J140 ft·lbf
30 J22.1 ft·lbf

Hardness, Brinell

215 HB
240 HB

Hardness, Rockwell B

88 HRB
99 HRB

Hardness, Vickers

230 HV
250 HV

Compressive Strength

—
450 MPa65.3 ksi

Same in both: Shear Modulus 77 GPa11.2 Msi

Physical

Density and transition temperatures.

Liquidus Temperature

1,450°C2,642 °F
1,420°C2,588 °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.

Thermal Conductivity

15 W/m·K8.7 BTU/hr·ft·°F
16.2 W/m·K9.4 BTU/hr·ft·°F

Thermal Expansion (CTE, 20–100 °C)

16 µm/m·K8.9 µin/in·°F
17.3 µm/m·K9.6 µin/in·°F

Latent Heat of Fusion

280 J/g120 BTU/lb
275 J/g118 BTU/lb

Min Service Temperature

-196°C-321 °F
-100°C-148 °F

Same in both: Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F · Max Service Temperature (continuous) 760°C1,400 °F

Electrical

Conductivity and insulation.

Electrical Resistivity

7.3×10⁻⁷ Ω·m28.7 µΩ·in
7.2×10⁻⁷ Ω·m28.3 µΩ·in

Same in both: Electrical Conductivity 2.4 % IACS

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.05 V
-0.1 V

Corrosion Resistance

56 / 100
58 / 100

Manufacturability

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

Machinability

38 / 100
72 / 100

Machinability Rating (AISI 1212 = 100 %)

45%
78%

Weldability

80 / 100
25 / 100

Formability (cold)

88 / 100
40 / 100

Brazeability / Solderability

65 / 100
60 / 100

Polishability

80 / 100
40 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Carbon (primary production)

4.3 kg CO₂/kg
5.5 kg CO₂/kg

Embodied Water

120 L/kg14.4 gal/lb
150 L/kg18 gal/lb

Typical Recycled Content

60%
65%

Same in both: Embodied Energy (primary production) 53 MJ/kg22,786 BTU/lb

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

95 kN·m/kg
83 kN·m/kg

Specific Stiffness (E / density)

25.3 MN·m/kg
24.4 MN·m/kg

Modulus of Resilience

400 kJ/m³
525 kJ/m³

Thermal Diffusivity

3.8 mm²/s
4.1 mm²/s

Thermal Shock Resistance Index

4
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 scale303301LN

Manufacturing and finishing

Capability301LN303
CNC machining—Yes
Default condition—Cold Drawn
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.

301LN vs 303 — frequently asked

Is 303 stronger than 301LN?

Yes. 303 has a typical yield strength of 450 MPa (65.3 ksi) against 400 MPa (58 ksi) for 301LN — about 13% more. Tensile strength is 655 MPa (95 ksi) vs 750 MPa (109 ksi).

Which is cheaper, 301LN or 303?

301LN 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, 301LN or 303?

303. Its machinability rates very good (72/100) against fair (38/100) for 301LN; for welding the order is 301LN first (very good, 80/100) then 303 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 301LN and 303 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.