304 and 316 are the two most widely used stainless steels. They look identical, but 316 adds molybdenum for far better corrosion resistance in harsh environments.
| Property | undefined | undefined |
|---|---|---|
| Composition | 18% Cr, 8% Ni | 16% Cr, 10% Ni, 2 to 3% Mo |
| Corrosion resistance | Good | Excellent, resists chlorides |
| Yield strength | About 215 MPa | About 205 MPa |
| Cost | Lower | Higher, 20 to 30% more |
| Magnetic | No (austenitic) | No (austenitic) |
| Typical use | Kitchen, architectural, general | Marine, chemical, medical |
Which should you choose
Choose 304 for everyday use such as food equipment, fasteners, and architectural trim, where it offers great corrosion resistance at a lower price.
Choose 316 when chlorides are present, as in saltwater, pools, or chemical processing. The added molybdenum resists the pitting that would attack 304.
Molybdenum makes the difference. The 2 to 3 percent molybdenum in 316 is what defeats chloride pitting. For marine and chemical use, pay for 316; otherwise 304 is plenty.
Compare data sheets: 304 Stainless Steel and 316 Stainless Steel.