304 vs 316L Stainless Steel: A Practical Selection Guide
304 vs 316L Stainless Steel: A Practical Selection Guide
304 and 316L are the two most common austenitic stainless grades. They look almost identical but behave differently in corrosive service. Specifying the right one prevents premature failure — and overspending on 316L when 304 would do.
What Makes Them Different
Both are 18 % Cr – 8 % Ni alloys. The key difference is molybdenum: 316L adds 2.0 – 2.5 % モー, which greatly improves resistance to pitting and crevice corrosion in chloride environments. の “L” means low carbon (≤ 0.030 %), which prevents sensitization after welding.
| 財産 | 304 | 316L |
|---|---|---|
| Cr ( % ) | 18 – 20 | 16 – 18 |
| で ( % ) | 8 – 10.5 | 10 – 14 |
| モー ( % ) | — | 2.0 – 2.5 |
| Pitting resistance | Good in clean air/water | Excellent in chloride / salt |
Use 304 When
304 is the default for indoor, architectural and food-contact use: キッチン用品, railings, decorative trim, sheet and plate. See our 304 シート, 304 channel と 304 floor plate.
Use 316L When
Step up to 316L for marine, coastal, chemical, pharmaceutical and outdoor splash zones. The low carbon “L” also helps when welded components cannot be post-weld annealed. See our 316L plate, 316L round bar, 316L flat bar と 316L welded pipe.
進捗