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Stainless Steel 303 vs 316LN

Stainless Steel · grade comparison

Stainless Steel 303 and 316LN 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 316LN, about 41% more; tensile strength follows at 655 MPa (95 ksi) vs 610 MPa (88.5 ksi). In exchange, 316LN is the more ductile: elongation 48% versus 30% for 303, and 303 is harder (240 HB vs 165 HB). 303 conducts heat better (16.2 W/m·K vs 14.5 W/m·K). On the shop floor, 303 machines more easily (very good vs fair) and 316LN welds better (excellent vs poor).

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

316LNChoose it when the part is bent, formed or impact-loaded, or when it will be welded.

303 vs 316LN: properties

303316LN

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Elastic (Young's) Modulus

193 GPa28 Msi
196 GPa28.4 Msi

Bulk Modulus

140 GPa20.3 Msi
166 GPa24.1 Msi

Poisson's Ratio

0.29
0.3

Tensile Strength (Ultimate)

655 MPa95 ksi
610 MPa88.5 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
320 MPa46.4 ksi

Elongation at Break

30%
48%

Reduction in Area

50%
68%

Compressive Strength

450 MPa65.3 ksi
320 MPa46.4 ksi

Fatigue Strength (Endurance Limit)

270 MPa39.2 ksi
250 MPa36.3 ksi

Fracture Toughness (K_IC)

100 MPa·√m91 ksi·√in
200 MPa·√m182 ksi·√in

Charpy V-Notch Impact (RT)

30 J22.1 ft·lbf
160 J118 ft·lbf

Hardness, Brinell

240 HB
165 HB

Hardness, Rockwell B

99 HRB
85 HRB

Hardness, Vickers

250 HV
175 HV

Same in both: Shear Modulus 77 GPa11.2 Msi · Shear Strength 420 MPa60.9 ksi

Physical

Density and transition temperatures.

Density

7.9 g/cm³0.29 lb/in³
8 g/cm³0.29 lb/in³

Melting Point (Solidus)

1,400°C2,552 °F
1,390°C2,534 °F

Liquidus Temperature

1,420°C2,588 °F
1,440°C2,624 °F

Thermal

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

Thermal Conductivity

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

Thermal Expansion (CTE, 20–100 °C)

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

Latent Heat of Fusion

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

Max Service Temperature (continuous)

760°C1,400 °F
800°C1,472 °F

Min Service Temperature

-100°C-148 °F
-196°C-321 °F

Same in both: Specific Heat Capacity 500 J/kg·K0.12 BTU/lb·°F

Electrical

Conductivity and insulation.

Electrical Conductivity

2.4 % IACS
2.3 % IACS

Electrical Resistivity

7.2×10⁻⁷ Ω·m28.3 µΩ·in
7.5×10⁻⁷ Ω·m29.5 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.1 V
-0.08 V

Corrosion Resistance

58 / 100
72 / 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%
33%

Weldability

25 / 100
90 / 100

Formability (cold)

40 / 100
78 / 100

Polishability

40 / 100
82 / 100

Same in both: Brazeability / Solderability 60 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

53 MJ/kg22,786 BTU/lb
78 MJ/kg33,534 BTU/lb

Embodied Carbon (primary production)

5.5 kg CO₂/kg
5.2 kg CO₂/kg

Same in both: Embodied Water 150 L/kg18 gal/lb · Typical Recycled Content 65%

Common Calculations

Ratios derived from the values above.

Specific Strength (UTS / density)

83 kN·m/kg
76 kN·m/kg

Specific Stiffness (E / density)

24.4 MN·m/kg
24.5 MN·m/kg

Modulus of Resilience

525 kJ/m³
261 kJ/m³

Thermal Diffusivity

4.1 mm²/s
3.6 mm²/s

Same in both: 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 scale303316LN

Manufacturing and finishing

Capability303316LN
Sheet metal—Yes
Default conditionCold DrawnSolution Annealed
Relative cost$$$ Premium$$$ Premium
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm

Both are offered for CNC machining. Both take the same 32 finishes: AlCrN, AlTiN, Black Oxide, CVD Al2O3, CVD TiCN, CVD TiN, Cerakote, Chrome Plating, CrN, DLC, Electroless Nickel (EN), Electropolishing and 20 more.

303 vs 316LN — frequently asked

Is 303 stronger than 316LN?

Yes. 303 has a typical yield strength of 450 MPa (65.3 ksi) against 320 MPa (46.4 ksi) for 316LN — about 41% more. Tensile strength is 655 MPa (95 ksi) vs 610 MPa (88.5 ksi).

Which is cheaper, 303 or 316LN?

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, 303 or 316LN?

303. Its machinability rates very good (72/100) against fair (38/100) for 316LN; for welding the order is 316LN first (excellent, 90/100) then 303 (poor, 25/100).

Ready to make it?

Upload a CAD file and FabDigit prices the part in 303 and 316LN 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.