| Attribute | SS304 | SS316 |
|---|---|---|
| Chemical Composition | 18-20% Cr, 8-10.5% Ni, up to 2% Mn, max 0.08% C | 16-18% Cr, 10-14% Ni, 2-3% Mo, up to 2% Mn, max 0.08% C |
| Corrosion Resistance | Good corrosion resistance in mildly corrosive environments | Superior corrosion resistance, especially in chloride-rich environments due to molybdenum content |
| Pitting Resistance | Susceptible to pitting in chloride environments | Excellent pitting resistance due to the presence of molybdenum |
| Stress Corrosion Cracking | Moderate resistance; can crack in high-stress, corrosive environments | Higher resistance to stress corrosion cracking, particularly in marine environments |
| Crevice Corrosion | Prone to crevice corrosion in tight, enclosed spaces | Greater resistance to crevice corrosion due to molybdenum |
| Temperature Resistance | Performs well at high temperatures up to 870°C | Performs well at high temperatures, slightly better than SS304 due to improved oxidation resistance |
| Applications | Used in general-purpose fasteners, automotive, kitchen equipment | Used in marine environments, chemical processing, and high-salinity applications |
| Cost | Lower cost compared to SS316, making it more economical for general applications | Higher cost due to the molybdenum content, justifiable in highly corrosive environments |
| Magnetic Properties | Non-magnetic in annealed condition, may become slightly magnetic when cold worked | Similar non-magnetic properties, with slightly lower magnetism after cold working |
| Weldability | Excellent weldability with no need for post-weld annealing | Also excellent weldability, but may require post-weld treatment in highly corrosive applications |
| Availability | Widely available and commonly used | Widely available, but less so than SS304 due to its specialized use cases |
| Mechanical Properties | Tensile Strength: 515 MPa, Yield Strength: 205 MPa, Elongation: 40% | Tensile Strength: 515 MPa, Yield Strength: 205 MPa, Elongation: 40% |
SS316 offers superior corrosion resistance in harsh environments, particularly in the presence of chlorides, making it ideal for fasteners in marine and chemical applications, while SS304 is cost-effective for less corrosive conditions.