FabDigitFabDigit

Stainless Steel 303 vs 316L

Stainless Steel · grade comparison

Stainless Steel 303 and 316L are both stainless steel grades. 303 is the stronger of the two: yield strength 450 MPa (65.3 ksi) against 290 MPa (42.1 ksi) for 316L, about 55% more; tensile strength follows at 655 MPa (95 ksi) vs 580 MPa (84.1 ksi). In exchange, 316L is the more ductile: elongation 50% versus 30% for 303, and 303 is harder (240 HB vs 150 HB). On the shop floor, 303 machines more easily (very good vs fair), 316L welds better (excellent vs poor), and 303 sits in a lower cost tier (premium, $$$) than 316L (high, $$$$).

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

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

303 vs 316L: properties

303316L

Mechanical

Strength, stiffness, ductility and hardness at room temperature.

Bulk Modulus

140 GPa20.3 Msi
166 GPa24.1 Msi

Poisson's Ratio

0.29
0.27

Tensile Strength (Ultimate)

655 MPa95 ksi
580 MPa84.1 ksi

Yield Strength (0.2% offset)

450 MPa65.3 ksi
290 MPa42.1 ksi

Elongation at Break

30%
50%

Reduction in Area

50%
65%

Compressive Strength

450 MPa65.3 ksi
290 MPa42.1 ksi

Shear Strength

420 MPa60.9 ksi
430 MPa62.4 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
130 J95.9 ft·lbf

Hardness, Brinell

240 HB
150 HB

Hardness, Rockwell B

99 HRB
80 HRB

Hardness, Vickers

250 HV
155 HV

Same in both: Elastic (Young's) Modulus 193 GPa28 Msi · Shear Modulus 77 GPa11.2 Msi

Physical

Density and transition temperatures.

Density

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

Melting Point (Solidus)

1,400°C2,552 °F
1,375°C2,507 °F

Liquidus Temperature

1,420°C2,588 °F
1,400°C2,552 °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
15 W/m·K8.7 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
7.4×10⁻⁷ Ω·m29.1 µΩ·in

Chemical & Environmental

Corrosion and environmental resistance (0–100 scores).

Galvanic Potential (seawater, vs SCE)

-0.1 V
-0.05 V

Corrosion Resistance

58 / 100
75 / 100

Manufacturability

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

Machinability

72 / 100
40 / 100

Machinability Rating (AISI 1212 = 100 %)

78%
45%

Weldability

25 / 100
90 / 100

Formability (cold)

40 / 100
85 / 100

Brazeability / Solderability

60 / 100
70 / 100

Polishability

40 / 100
85 / 100

Castability

—
50 / 100

Sustainability

Primary-production footprint per kilogram.

Embodied Energy (primary production)

53 MJ/kg22,786 BTU/lb
75 MJ/kg32,244 BTU/lb

Embodied Carbon (primary production)

5.5 kg CO₂/kg
5.3 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
73 kN·m/kg

Specific Stiffness (E / density)

24.4 MN·m/kg
24.2 MN·m/kg

Modulus of Resilience

525 kJ/m³
218 kJ/m³

Thermal Diffusivity

4.1 mm²/s
3.8 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 scale303316L

Manufacturing and finishing

Capability303316L
Sheet metal—Yes
3D printing—Yes
Default conditionCold DrawnSolution Annealed
Relative cost$$$ Premium$$$$ High
Min. machined wall0.8 mm0.8 mm
Best machined surfaceRa 1.6 µmRa 1.6 µm
Electropolished (Metal AM)—Yes
Passivated (Metal AM)—Yes
Plated (Metal AM)—Yes

Both are offered for CNC machining. They share 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 316L — frequently asked

Is 303 stronger than 316L?

Yes. 303 has a typical yield strength of 450 MPa (65.3 ksi) against 290 MPa (42.1 ksi) for 316L — about 55% more. Tensile strength is 655 MPa (95 ksi) vs 580 MPa (84.1 ksi).

Which is cheaper, 303 or 316L?

303 is the lower-cost material: it sits in the premium tier ($$$) while 316L is high ($$$$). 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 316L?

303. Its machinability rates very good (72/100) against fair (40/100) for 316L; for welding the order is 316L 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 316L 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.