A351 CF8M vs 316
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.
A351 CF8M
Stainless Steel
ASTM A351 CF8M is the cast equivalent of 316 stainless — the molybdenum-bearing grade for chloride-bearing process streams, seawater-adjacent equipment and chemical valves where CF8 pits. It is the most common stainless casting grade in refinery and chemical service.
Standards: DIN 1.4408 (GX5CrNiMo19-11-2) · AISI A351 CF8M · JIS SCS14A · GB ZG0Cr17Ni12Mo2 (legacy, near)
316
Stainless Steel
316 adds 2–3% molybdenum to the 18-10 base of 304, which markedly improves pitting and crevice corrosion resistance in chloride media. It is the standard marine and chemical-process stainless.
Standards: DIN 1.4401 · AISI 316 · JIS SUS316 · GB 06Cr17Ni12Mo2
Chemical composition compared (%)
| Element | A351 CF8M | 316 |
|---|---|---|
| C | ≤0.08 | ≤0.08 |
| Si | ≤1.50 | ≤0.75 |
| Mn | ≤1.50 | ≤2.00 |
| P | ≤0.040 | ≤0.045 |
| S | ≤0.040 | ≤0.030 |
| Cr | 18.00–21.00 | 16.00–18.00 |
| Ni | 9.00–12.00 | 10.00–14.00 |
| Mo | 2.00–3.00 | 2.00–3.00 |
| N | — | ≤0.10 |
Properties compared
| Property | A351 CF8M | 316 |
|---|---|---|
| Tensile strength | ≥485 MPa | 515–690 MPa |
| Yield strength | ≥205 MPa | ≥205 MPa |
| Elongation | ≥30% | — |
| Density | 7.90 g/cm³ | 7.90 g/cm³ |
| Delivery condition | — | Annealed |
| Hardness | — | ≤217 HB (annealed) |
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: A351 CF8M · 316. Substitution decisions for certified parts stay with the design authority.