Stainless Steel 316L
Stainless Steel 316L (UNS S31603 / EN 1.4404) – Specifications, Properties and Applications
Stainless Steel 316L (UNS S31603 / EN 1.4404) is a low-carbon, molybdenum-bearing austenitic stainless steel developed for applications requiring excellent corrosion resistance, superior weldability, and reliable performance in aggressive environments.
The addition of molybdenum provides enhanced resistance to pitting and crevice corrosion, particularly in chloride-containing environments, seawater, and industrial chemicals. The low carbon content reduces the risk of chromium carbide precipitation during welding, making 316L an excellent choice for welded structures and process equipment.
Stainless Steel 316L is widely used in chemical processing, petrochemical plants, marine engineering, pharmaceutical manufacturing, food processing, water treatment, desalination, power generation, and industrial piping systems.
Emirerri Steel supplies Stainless Steel 316L in sheets, plates, coils, pipes, tubes, round bars, flanges, and pipe fittings for customers in Tunisia, Algeria, Morocco, Libya, and international markets.
Key Features
- Excellent general corrosion resistance
- Superior resistance to chloride environments
- Excellent resistance to pitting corrosion
- Good resistance to crevice corrosion
- Low carbon content
- Excellent resistance to intergranular corrosion after welding
- Excellent weldability
- Good formability
- Good mechanical strength
- Excellent toughness
- Long service life
- Low maintenance requirements
Stainless Steel 316L Specifications
| Specification | Details |
|---|---|
| Grade | Stainless Steel 316L |
| UNS Number | S31603 |
| Werkstoff Number | 1.4404 |
| EN Designation | X2CrNiMo17-12-2 |
| Stainless Steel Family | Austenitic Stainless Steel |
| Common Standards | ASTM A240, ASTM A276, ASTM A312, ASTM A182, ASTM A213, ASTM A269, EN 10088 |
| Supply Condition | Solution Annealed |
| Surface Finishes | No.1, 2B, BA, No.4, Mirror |
| Product Forms | Sheet, Plate, Coil, Pipe, Tube, Round Bar, Flanges, Pipe Fittings |
Equivalent Grades of Stainless Steel 316L
| Standard | Equivalent Grade |
|---|---|
| ASTM | 316L |
| UNS | S31603 |
| EN | 1.4404 |
| DIN | X2CrNiMo17-12-2 |
| JIS | SUS316L |
| ISO | X2CrNiMo17-12-2 |
Available Sizes
Sheets & Plates
- Thickness: 0.5 to 100 mm
- Width: Up to 2500 mm
- Length: Up to 12000 mm
Pipes & Tubes
- Outside Diameter: 6 to 610 mm
- Wall Thickness: 0.5 to 40 mm
Round Bars
Diameter: 6 to 500 mm
Actual availability depends on product form, applicable standard, manufacturing route, and project requirements.
Chemical Composition of Stainless Steel 316L
| Element | Composition (%) |
|---|---|
| Chromium (Cr) | 16.0 – 18.0 |
| Nickel (Ni) | 10.0 – 14.0 |
| Molybdenum (Mo) | 2.0 – 3.0 |
| Carbon (C) | ≤ 0.030 |
| Manganese (Mn) | ≤ 2.00 |
| Silicon (Si) | ≤ 1.00 |
| Phosphorus (P) | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 |
| Nitrogen (N) | ≤ 0.10 |
| Iron (Fe) | Balance |
Mechanical Properties of Stainless Steel 316L
Typical minimum values for annealed products under commonly used ASTM specifications include:
| Property | Value |
|---|---|
| Tensile Strength | ≥ 485 MPa |
| Yield Strength (0.2% Offset) | ≥ 170 MPa |
| Elongation | ≥ 40% |
| Hardness | ≤ 217 HB |
| Modulus of Elasticity | ≈ 193 GPa |
Physical Properties of Stainless Steel 316L
| Property | Approximate Value |
|---|---|
| Density | 8.00 g/cm³ |
| Melting Range | ≈ 1375 – 1400°C |
| Thermal Conductivity | ≈ 16.3 W/m·K |
| Specific Heat Capacity | ≈ 500 J/kg·K |
| Electrical Resistivity | ≈ 0.74 µΩ·m |
| Magnetic Permeability | Low in Annealed Condition |
Types of Stainless Steel 316L Products
Stainless Steel 316L Sheets & Plates
- Used for chemical tanks, pressure vessels, pharmaceutical equipment, food-processing machinery, and industrial fabrication.
Stainless Steel 316L Pipes & Tubes
- Suitable for process piping, marine systems, chemical transportation, water treatment, and fluid-handling applications.
Stainless Steel 316L Heat Exchanger Tubes
- Used in heat exchangers, condensers, cooling systems, and thermal-processing equipment.
Stainless Steel 316L Round Bars
- Used for shafts, valves, pumps, fasteners, machined components, and industrial equipment.
Stainless Steel 316L Flanges & Pipe Fittings
- Designed for piping systems in chemical, petrochemical, marine, pharmaceutical, food-processing, and water-treatment industries.
Corrosion Resistance
Stainless Steel 316L offers excellent resistance to:
- General corrosion
- Pitting corrosion
- Crevice corrosion
- Chloride-containing environments
- Seawater and coastal atmospheres
- Many organic and inorganic chemicals
- Industrial process fluids
- Corrosion in welded areas
The molybdenum content provides significantly improved resistance to localized corrosion compared with 304 and 304L stainless steel.
Its low carbon content also minimizes chromium carbide precipitation during welding, reducing the risk of intergranular corrosion in welded components.
Heat Resistance
Stainless Steel 316L provides good oxidation resistance and maintains useful mechanical properties at elevated temperatures.
Service Temperature
- Continuous Service: Up to approximately 870°C
- Intermittent Service: Up to approximately 925°C
For applications requiring exceptional resistance to prolonged exposure at very high temperatures, heat-resistant grades such as 310S may be more appropriate.
Heat Treatment
Solution Annealing
Temperature: 1010 – 1120°C
Cooling: Rapid cooling, generally water quenching or as specified by the applicable standard
Objectives
Restore corrosion resistance
Improve ductility
Relieve internal stresses
Optimize microstructure
Stainless Steel 316L cannot be hardened by conventional heat treatment. It can, however, be strengthened through cold working.
Welding of Stainless Steel 316L
Stainless Steel 316L has excellent weldability and can be welded using most conventional welding processes.
Recommended Welding Methods
- GTAW / TIG
- GMAW / MIG
- SMAW
- SAW
- Orbital Welding
- Resistance Welding
Welding Advantages
- Excellent weld quality
- Low risk of intergranular corrosion
- Generally no preheating required
- Good post-weld corrosion resistance
- Excellent mechanical performance
Post-weld cleaning, pickling, and passivation are recommended where required by the service environment and applicable specifications.
Fabrication of Stainless Steel 316L
Machining
Turning
Milling
Drilling
Threading
Forming
Cold bending
Roll forming
Press forming
Deep drawing
Stretch forming
Cutting
Laser cutting
Plasma cutting
Waterjet cutting
Mechanical sawing
Surface Finishing
Pickling
Passivation
Mechanical polishing
Electropolishing
Brushing
Applications
Chemical Industry
Chemical storage tanks
Reactors
Process piping
Pressure vessels
Processing equipment
Petrochemical Industry
Refineries
Heat exchangers
Process piping
Chemical transportation systems
Marine Industry
Marine piping
Offshore equipment
Shipbuilding components
Port and coastal equipment
Pharmaceutical Industry
Hygienic vessels
Production equipment
Storage tanks
Sanitary piping
Food & Beverage Industry
Food-processing equipment
Dairy equipment
Storage vessels
Hygienic piping systems
Water Treatment & Desalination
Desalination plants
Water treatment systems
Filtration equipment
Fluid transportation systems
Power Generation
Cooling systems
Industrial piping
Heat exchangers
Auxiliary process equipment
Stainless Steel 316L for Tunisia, Algeria, Morocco & Libya
Stainless Steel 316L is particularly suitable for industrial projects across Tunisia, Algeria, Morocco, and Libya where resistance to corrosion, chlorides, industrial chemicals, and coastal environments is required.
It is widely applicable to oil & gas, petrochemical, chemical processing, water treatment and desalination, marine, food processing, pharmaceutical, and power-generation projects.
For project applications, the final grade, product form, dimensions, and applicable standard should be selected according to the operating temperature, pressure, chloride concentration, process fluid, fabrication method, and project specifications.
Conclusion
Stainless Steel 316L (UNS S31603 / EN 1.4404) is a low-carbon molybdenum-bearing austenitic stainless steel offering excellent corrosion resistance, superior resistance to pitting and crevice corrosion, and outstanding weldability. Its low carbon content makes it particularly suitable for welded structures where resistance to intergranular corrosion is important.
Available in sheets, plates, pipes, tubes, round bars, flanges, and pipe fittings, Stainless Steel 316L is a reliable material for demanding applications in chemical processing, petrochemical, marine, pharmaceutical, food, water treatment, desalination, and power-generation industries across Tunisia, Algeria, Morocco, Libya, and global markets.