AISI 304L (S30403) Stainless Steel
AISI 304L stainless steel is an austenitic stainless steel formulated for primary forming into wrought products. 304L is the AISI designation for this material. S30403 is the UNS number. Additionally, the British Standard (BS) designation is 304S12.
This material is well established: the Further Reading section below cites a number of published standards, and that list is not necessarily exhaustive.
The properties of AISI 304L stainless steel include seven common variations. This page shows summary ranges across all of them. For more specific values, follow the links immediately below. The graph bars on the material properties cards further below compare AISI 304L stainless steel to: wrought austenitic stainless steels (top), all iron alloys (middle), and the entire database (bottom). A full bar means this is the highest value in the relevant set. A half-full bar means it's 50% of the highest, and so on.
Mechanical Properties
Brinell Hardness
160 to 350
Elastic (Young's, Tensile) Modulus
200 GPa 29 x 106 psi
Elongation at Break
6.7 to 46 %
Fatigue Strength
170 to 430 MPa 25 to 62 x 103 psi
Poisson's Ratio
0.28
Rockwell B Hardness
79
Shear Modulus
77 GPa 11 x 106 psi
Shear Strength
370 to 680 MPa 54 to 98 x 103 psi
Tensile Strength: Ultimate (UTS)
540 to 1160 MPa 78 to 170 x 103 psi
Tensile Strength: Yield (Proof)
190 to 870 MPa 28 to 130 x 103 psi
Thermal Properties
Latent Heat of Fusion
290 J/g
Maximum Temperature: Corrosion
420 °C 790 °F
Maximum Temperature: Mechanical
540 °C 1000 °F
Melting Completion (Liquidus)
1450 °C 2640 °F
Melting Onset (Solidus)
1400 °C 2550 °F
Specific Heat Capacity
480 J/kg-K 0.11 BTU/lb-°F
Thermal Conductivity
16 W/m-K 9.2 BTU/h-ft-°F
Thermal Expansion
17 µm/m-K
Electrical Properties
Electrical Conductivity: Equal Volume
2.4 % IACS
Electrical Conductivity: Equal Weight (Specific)
2.7 % IACS
Otherwise Unclassified Properties
Base Metal Price
16 % relative
Calomel Potential
-80 mV
Density
7.8 g/cm3 490 lb/ft3
Embodied Carbon
3.1 kg CO2/kg material
Embodied Energy
44 MJ/kg 19 x 103 BTU/lb
Embodied Water
150 L/kg 18 gal/lb
Common Calculations
PREN (Pitting Resistance)
20
Resilience: Ultimate (Unit Rupture Work)
71 to 240 MJ/m3
Resilience: Unit (Modulus of Resilience)
92 to 1900 kJ/m3
Stiffness to Weight: Axial
14 points
Stiffness to Weight: Bending
25 points
Strength to Weight: Axial
19 to 41 points
Strength to Weight: Bending
19 to 31 points
Thermal Diffusivity
4.2 mm2/s
Thermal Shock Resistance
12 to 25 points
Alloy Composition
Among wrought stainless steels, the composition of AISI 304L stainless steel is notable for containing comparatively high amounts of chromium (Cr) and nickel (Ni). Chromium is the defining alloying element of stainless steel. Higher chromium content imparts additional corrosion resistance. Nickel is primarily used to achieve a specific microstructure. In addition, it has a beneficial effect on mechanical properties and certain types of corrosion.
| Fe | 65 to 74 | |
| Cr | 18 to 20 | |
| Ni | 8.0 to 12 | |
| Mn | 0 to 2.0 | |
| Si | 0 to 0.75 | |
| N | 0 to 0.1 | |
| P | 0 to 0.045 | |
| C | 0 to 0.030 | |
| S | 0 to 0.030 |
All values are % weight. Ranges represent what is permitted under applicable standards.
Followup Questions
Similar Alloys
Further Reading
ASTM A493: Standard Specification for Stainless Steel Wire and Wire Rods for Cold Heading and Cold Forging
ASTM A473: Standard Specification for Stainless Steel Forgings
ASTM A479: Standard Specification for Stainless Steel Bars and Shapes for Use in Boilers and Other Pressure Vessels
ASTM A666: Standard Specification for Annealed or Cold-Worked Austenitic Stainless Steel Sheet, Strip, Plate, and Flat Bar
ASTM A182: Standard Specification for Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Forged Fittings, and Valves and Parts for High-Temperature Service
ASTM A276: Standard Specification for Stainless Steel Bars and Shapes
ASTM A240: Standard Specification for Chromium and Chromium-Nickel Stainless Steel Plate, Sheet, and Strip for Pressure Vessels and for General Applications
Welding Metallurgy of Stainless Steels, Erich Folkhard et al., 2012
ASTM A959: Standard Guide for Specifying Harmonized Standard Grade Compositions for Wrought Stainless Steels
Corrosion of Austenitic Stainless Steels: Mechanism, Mitigation and Monitoring, H. S. Khatak and B. Raj (editors), 2002