317 vs 317L
These two grades are listed as equivalents of each other: their chemistry windows overlap and they serve the same applications. They are not always identical — check the differences below before substituting, especially in certified designs.
317
Stainless Steel
317 increases molybdenum to 3–4% over 316, giving a further step in pitting and acid resistance for aggressive chemical service. It sits between 316L and the 6% molybdenum super-austenitics.
Standards: DIN 1.4449 · AISI 317 · JIS SUS317 · GB 06Cr19Ni13Mo3
317L
Stainless Steel
317L is the low-carbon version of 317, with 3–4% molybdenum for welded equipment in hot chloride and acid service beyond the capability of 316L. Its PREN of about 30 bridges the gap to super-austenitic grades.
Standards: DIN 1.4438 · AISI 317L · JIS SUS317L · GB 022Cr19Ni13Mo3
Chemical composition compared (%)
| Element | 317 | 317L |
|---|---|---|
| C | ≤0.08 | ≤0.030 |
| Si | ≤0.75 | ≤0.75 |
| Mn | ≤2.00 | ≤2.00 |
| P | ≤0.045 | ≤0.045 |
| S | ≤0.030 | ≤0.030 |
| Cr | 18.00–20.00 | 18.00–20.00 |
| Ni | 11.00–15.00 | 11.00–15.00 |
| Mo | 3.00–4.00 | 3.00–4.00 |
| N | — | ≤0.10 |
Properties compared
| Property | 317 | 317L |
|---|---|---|
| Delivery condition | Annealed | Annealed |
| Hardness | ≤217 HB (annealed) | ≤217 HB (annealed) |
| Tensile strength | 515–690 MPa | 515–690 MPa |
| Density | 7.90 g/cm³ | 7.90 g/cm³ |
Sourcing either grade?
Nasteel stocks both families from Shenzhen with EN 10204 3.1 mill certificates by heat number.
Ask for a quotationSee full data sheets: 317 · 317L. Substitution decisions for certified parts stay with the design authority.